Add plain-language concept docs; fix docs viewer rendering; link API tokens

- New docs/concepts-{accounts,oauth-apps,api-tokens}.md -- plain-language
  guides aimed at less technical readers, each linking onward to the
  existing schema/protocol-level doc for anyone who wants that detail.
  Card help links (Users, Groups, OAuth cards, My groups, Members of
  <uid>'s group) now point here instead of straight at the technical
  docs; the LDAP-protocol-wiring cards (raw connection details for
  connecting a 3rd-party app) stay pointed at the technical ldap.md,
  since that's genuinely the right depth for that task.
- The "New API Token" card had no help link at all -- added, pointing to
  the new API Tokens doc.
- Fixed the in-app docs viewer rendering every docs/*.md page with a
  garbled heading + stray <hr> at the top: Jekyll front matter (meant
  only for the GitHub Pages build) was never stripped before being
  handed to the markdown renderer. Also fixed: cross-doc links
  (ldap.html, index.html, etc.) never resolved in-app, since this
  viewer serves docs at /docs/<slug> with no .html suffix -- rewritten
  to the correct in-app URL, same idea as the existing image-path fix.

Bumps to v1.1.12.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KDEx8ghuZR61pqPXc6da9C

docs/concepts-accounts.md

@@ -0,0 +1,102 @@
+---
+layout: default
+title: Accounts, Groups & Managers
+description: A plain-language guide to users, service accounts, personal groups, and managers in SSO Manager.
+---
+
+# Accounts, Groups & Managers
+
+This page explains the concepts behind the Users and Groups pages in plain
+language. If you want the technical schema/attribute-level detail instead,
+see the [LDAP reference](ldap.html).
+
+## What's an account?
+
+Every person (or app) that can sign in through this SSO Manager has an
+**account** — a username, a display name, maybe an email address, and a
+password (or, for service accounts, no password at all — see below).
+Accounts live in the directory this app manages, and any other app you've
+connected (Gitea, Home Assistant, your Wi-Fi, whatever) checks against these
+same accounts instead of keeping its own separate list of users and
+passwords.
+
+## Two kinds of account: people and service accounts
+
+Most accounts belong to an actual person — check **Users → People** to see
+them. But sometimes you need an account for something that *isn't* a
+person: a media server, a backup script, a bind account another app uses to
+look people up. These are **service accounts**, listed separately under
+**Users → Service Accounts**, and they're different from a person's account
+in two ways that matter:
+
+- **No email required.** A service account doesn't need a mailbox, so the
+  form doesn't ask for one.
+- **A password is optional.** If you leave it blank, nobody can log in as
+  that account — which is exactly what you want for something that only
+  ever gets used programmatically (a script authenticating with an API
+  token, or another app binding with a fixed, separately-configured
+  password you set yourself). Only give it a password if the account
+  genuinely needs to log in or bind somewhere as itself.
+
+Aside from those two differences, a service account is a completely normal
+account under the hood — it can belong to groups, have a manager, and so
+on, just like anyone else's.
+
+## Groups: who can do what
+
+A **group** is just a named list of accounts, used to control access. This
+app has a handful of built-in groups that grant admin powers (e.g. only
+people in the `app_sso_admin` group can see the Users/Groups/Integrations
+pages at all), but you can also make your own groups for any app you
+connect — say, a group listing everyone who should be allowed into your
+photo server. Once a group exists, add or remove members from the
+**Groups** page, and point the other app's "who's allowed in" setting at
+that group's name.
+
+## Every account's personal group
+
+Separately from the groups above, every single account — person or
+service account — automatically gets its own small, personal group when
+it's created, named after the account itself. Most of the time you'll
+never think about this; it exists so that, on a Linux system connected to
+this directory, each account "owns" its own files by default the same way
+a normal Unix user account would.
+
+Occasionally you'll want to share that ownership with someone else — for
+example, letting a second account also have write access to files a
+service account owns. That's what the **"Members of `<uid>`'s group"**
+section on a profile page is for: add another account there, and the
+underlying Linux permissions treat them as if they belong to that same
+personal group too.
+
+## What's a "manager"?
+
+Every account has one or more **managers** — the people allowed to edit
+that account's profile (phone number, SSH key, home directory, and so on)
+without needing full admin rights. By default, whoever created an account
+(the admin who added it, or whoever sent the invite) becomes its first
+manager, but you can add or remove managers later from the account's Edit
+form.
+
+This is useful for service accounts especially: if a service account
+belongs to a particular project or person, make them its manager so they
+can maintain it — rotate its SSH key, adjust its description — without
+needing to be a full SSO administrator.
+
+## Inviting someone vs. adding them yourself
+
+From the Users page you can either fill in someone's details yourself
+("Add new user"), or send them an **invite** — an email (or a link you copy
+and send however you like) that lets them pick their own username and
+password. Either way, the resulting account is identical; invites are just
+a convenience so you don't have to know someone's preferred username or
+handle their password directly.
+
+## Want more detail?
+
+This page deliberately leaves out LDAP schema names, attribute types, and
+protocol-level detail. If you're connecting a third-party app directly to
+the LDAP directory, or you just want to know exactly what's stored where,
+see the [LDAP reference](ldap.html).
+
+[← Back to Home](index.html)

docs/concepts-api-tokens.md

@@ -0,0 +1,59 @@
+---
+layout: default
+title: API Tokens
+description: A plain-language guide to personal access tokens in SSO Manager.
+---
+
+# API Tokens
+
+This page explains what an API token is and when you'd want one. For the
+full list of API endpoints a token can call, see the
+[API reference](api.html).
+
+## What's an API token, in plain terms?
+
+Normally, you interact with this app by logging in through a web browser.
+An **API token** (also called a personal access token, or PAT) is an
+alternative way in — a long, random string that a script, a scheduled job,
+or another program can use instead of a username and password, to act on
+your behalf without a human typing a login in each time.
+
+If you've ever set up a script to talk to GitHub, GitLab, or a similar
+service using a "token" instead of your real password, this is the same
+idea.
+
+## When would you actually need one?
+
+Most people never need to create one of these — you'll only want a token
+if you're automating something, for example:
+
+- A script that syncs users or groups from somewhere else into this SSO
+  Manager on a schedule.
+- A backup or monitoring job that checks this app's health via its API.
+- A CI/CD pipeline that needs to register or update an OAuth client
+  automatically.
+
+If you're not doing any of that, you don't need an API token — just log in
+normally through the web UI.
+
+## How it works
+
+Create a token from your Profile page, give it a name so you remember what
+it's for later, and optionally an expiry. You'll be shown the token's
+value **exactly once** — copy it somewhere safe immediately, because it
+can't be viewed again afterward (only revoked or rotated). Whatever script
+or tool you're using it with sends it along with each request, the same
+way a browser sends your login session.
+
+A token acts **as you**, with **your** permissions — if you're not an
+admin, a token you create can't do admin-only things either. If you ever
+suspect a token has leaked (ended up somewhere it shouldn't have, like a
+public script or log file), revoke it immediately from your Profile page;
+it stops working right away.
+
+## Want more detail?
+
+This page doesn't attempt to list every API endpoint or show request/
+response examples — for that, see the full [API reference](api.html).
+
+[← Back to Home](index.html)

docs/concepts-oauth-apps.md

@@ -0,0 +1,79 @@
+---
+layout: default
+title: Connecting Apps (Single Sign-On)
+description: A plain-language guide to OAuth/OIDC clients and single sign-on in SSO Manager.
+---
+
+# Connecting Apps (Single Sign-On)
+
+This page explains, in plain language, what happens when you "connect" an
+app to your SSO Manager so people can log into it with their existing
+account. For the technical endpoint/token detail, see the
+[OAuth reference](oauth.html).
+
+## What does "single sign-on" actually mean?
+
+Instead of every app you run having its own separate list of usernames and
+passwords, they all check with this SSO Manager instead. You log in once,
+here, and any connected app trusts that login — no separate password to
+remember or manage for each one. If you ever need to lock someone out
+everywhere at once, you do it in one place (deactivate their account here)
+instead of hunting down every app individually.
+
+The technology behind this is called **OAuth 2.0** and **OpenID Connect
+(OIDC)** — you'll see both names used, often together, referring to the
+same thing. You don't need to understand the protocol to use this page;
+what matters practically is the handful of concepts below.
+
+## What's a "client"?
+
+Every app you connect is registered here as a **client** — a single entry
+on the Integrations page representing that one app. Registering a client
+gives you a **Client ID** and **Client Secret**: think of these like a
+username and password, but for the *app itself* rather than for a person.
+You paste them into the other app's own "Single Sign-On" or "OIDC" setup
+screen, along with the discovery URL shown at the top of this page, and
+that app is now able to ask this SSO Manager to authenticate people on its
+behalf.
+
+**Treat the Client Secret like a password** — anyone who has it can
+impersonate that app when talking to your SSO Manager. If you ever suspect
+it's leaked, rotate it from the client's card.
+
+## What are "scopes"?
+
+**Scopes** control what information a connected app is allowed to ask for
+about the person logging in — their username, email, group memberships,
+and so on. Most apps tell you exactly which scopes they need in their own
+setup instructions; when in doubt, the default set (`openid`, `profile`,
+`email`, `groups`) covers what nearly every app expects.
+
+## "Restrict to Groups"
+
+By default, *any* account with an SSO Manager login can sign into a
+connected app. If that's not what you want — say, a home automation
+dashboard that only certain family members should reach — set **Restrict
+to Groups** on that client to one of your [groups](concepts-accounts.html).
+Only members of that group will be allowed to log into that particular
+app; everyone else gets turned away at the login step, even though their
+SSO Manager account still works everywhere else.
+
+## Redirect URIs
+
+A **Redirect URI** is the exact web address the connected app wants people
+sent back to once they've logged in here — it's a security measure so an
+attacker can't trick the login flow into redirecting somewhere else. The
+app's own setup instructions will tell you this value; copy it in exactly
+as given. If the app is reachable via more than one hostname (for example,
+because it sits behind [theta42/proxy](https://theta42.github.io/proxy/)),
+this field supports wildcard patterns — see the inline help under the
+field itself for the exact syntax.
+
+## Want more detail?
+
+This page intentionally skips the protocol-level detail (exact endpoint
+URLs, token formats, claim names). If you're troubleshooting a connection
+or building something against the API directly, see the
+[OAuth reference](oauth.html).
+
+[← Back to Home](index.html)

docs/ldap.md

@@ -8,6 +8,10 @@ description: SSO Manager's bundled OpenLDAP directory — schema, service accoun
 
 [← Back to Home](index.html)
 
+> Looking for a plainer explanation of accounts, groups, and managers
+> instead of schema/attribute detail? See
+> [Accounts, Groups & Managers](concepts-accounts.html).
+
 SSO Manager runs an OpenLDAP directory holding your users and groups. The app
 authenticates against it over `localhost:389` (inside the all-in-one container)
 and exposes **LDAPS** (`ldaps://…:636`, TLS) for legacy apps that bind LDAP

docs/oauth.md

@@ -8,6 +8,10 @@ description: SSO Manager's OpenID Connect / OAuth 2.0 provider — discovery doc
 
 [← Back to Home](index.html)
 
+> Looking for a plainer explanation of clients/scopes/redirect URIs instead
+> of endpoint-level detail? See
+> [Connecting Apps (Single Sign-On)](concepts-oauth-apps.html).
+
 SSO Manager is an **OpenID Connect / OAuth 2.0 provider**: it issues its own
 access, refresh, and ID tokens that your apps can consume to authenticate
 users and authorize API calls. It also runs a full OpenLDAP directory, so it