Add LDAP-over-HTTPS API, agent secrets/IAM engines, and join key management

See CHANGELOG.md for the full breakdown. Summary:

- POST /api/v1/ldap/{bind,search}: LDAP-over-HTTPS so a client stops
  speaking raw LDAP and instead calls the SSO, which binds/searches its
  own OpenLDAP on the caller's behalf (DESIGN.md §3).
- LDAP byte-pump relay (utils/ldap_tunnel.js): forwards raw LDAP bytes
  from an agent's local socket into OpenLDAP over the existing agent WSS
  channel; the SSO never parses LDAP (DESIGN.md §4).
- POST /api/v1/agent/secrets: node-scoped OpenBao secret fetch for
  agents, enforced to each agent's own secret/data/nodes/<id>/* prefix
  (DESIGN.md §5).
- iam_apply signed command: push node-scoped IAM config (sudo rules, SSH
  keys, access control, revocation) to an agent (DESIGN.md §6).
- Agent capability badges on the Directory Metrics tab, sourced from the
  agent's own discovery frame.
- Join key management: GET /api/agent/join-keys/:id/agents (which hosts
  enrolled through a key) plus a Manage join keys table in the Install
  Agent modal with Revoke/Delete actions, confirmed inline per-row rather
  than a blocking native confirm() or the shared app.messages.confirm()
  banner (which desyncs across concurrent rows -- see CHANGELOG).
- docs/agents.md: capability matrix updated for the three new
  capabilities, a full secrets-engine walkthrough with screenshots
  (bash + Node consuming a rendered secret, plus the direct-API
  alternative), and the join-key reuse/UI/audit questions answered.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

nodejs/utils/agent_auth.js

@@ -0,0 +1,26 @@
+'use strict';
+
+// Authenticate an agent from a Bearer token (the same token the agent presents
+// on its WSS channel). Used by agent-facing REST endpoints (secrets, IAM) that
+// are NOT admin-gated — the caller is the agent itself, not an admin session.
+
+const { Agent } = require('../models/agent');
+
+// Resolve a Bearer token to its (non-revoked) Agent, or null. Every failure
+// collapses to null so a probing caller learns nothing about which part was
+// wrong.
+async function authenticateAgent(req) {
+	const auth = req.headers['authorization'] || '';
+	const m = /^Bearer\s+(.+)$/i.exec(auth);
+	if (!m) return null;
+	const token = String(m[1]).trim();
+	if (!token) return null;
+	try {
+		const agent = await Agent.authenticate(token);
+		return agent || null;
+	} catch (_) {
+		return null;
+	}
+}
+
+module.exports = { authenticateAgent };

nodejs/utils/agent_manager.js

@@ -120,7 +120,10 @@ class AgentManager {
       cpu: payload.cpu || '',
       ram_total_gb: payload.ram_total_gb || 0,
       disk_total_gb: payload.disk_total_gb || 0,
-      location: payload.location || 'default'
+      location: payload.location || 'default',
+      // The agent's enabled capabilities (from its local agent.yml). The agent
+      // is the authoritative source for what it will actually do.
+      capabilities: payload.capabilities || {}
     };
     await this.touch(agent, { lastDiscovery: discovery });
     await this.applyDiscoveryToDirectory(agent, discovery);

nodejs/utils/ldap_tunnel.js

@@ -0,0 +1,84 @@
+'use strict';
+
+// LDAP byte-pump relay (DESIGN.md §4). The agent forwards raw LDAP bytes from a
+// local socket (SSSD) over the WSS channel as `ldap_tunnel` messages; this
+// module relays them into the SSO's real OpenLDAP and pipes the responses back.
+// The SSO does not parse LDAP either — it is a transparent socket relay.
+
+const net = require('net');
+const conf = require('@simpleworkjs/conf').ldap;
+
+// Parse host:port from an ldap:// or ldaps:// URL. The relay connects plaintext
+// to the SSO's own slapd (which is plaintext on localhost); an ldaps:// URL
+// would need TLS termination here and is not supported yet (DESIGN.md §9.5).
+function ldapTarget() {
+	const url = conf.url || 'ldap://localhost:389';
+	const m = /^ldaps?:\/\/([^:/]+)(?::(\d+))?/.exec(url);
+	const host = m ? m[1] : 'localhost';
+	const port = m && m[2] ? Number(m[2]) : 389;
+	return { host, port };
+}
+
+// Per-agent relay state: agentId -> Map(conn_id -> LDAP socket).
+const relays = new Map();
+
+function relayFor(agentId) {
+	if (!relays.has(agentId)) relays.set(agentId, new Map());
+	return relays.get(agentId);
+}
+
+// Handle one ldap_tunnel message from an agent.
+function handleTunnel(agentId, ws, payload) {
+	const connId = payload.conn_id;
+	if (!connId) return;
+	const conns = relayFor(agentId);
+
+	// End of connection: close the relay socket.
+	if (payload.close) {
+		const sock = conns.get(connId);
+		if (sock) { sock.destroy(); conns.delete(connId); }
+		return;
+	}
+
+	const data = Buffer.from(payload.data || '', 'base64');
+	if (data.length === 0) return;
+
+	let sock = conns.get(connId);
+	if (!sock) {
+		const { host, port } = ldapTarget();
+		sock = net.connect(port, host);
+		conns.set(connId, sock);
+
+		// Relay OpenLDAP's responses back to the agent.
+		sock.on('data', (chunk) => {
+			if (ws.readyState === 1) {
+				ws.send(JSON.stringify({
+					type: 'ldap_tunnel',
+					payload: { conn_id: connId, data: chunk.toString('base64') }
+				}));
+			}
+		});
+		sock.on('close', () => {
+			conns.delete(connId);
+			if (ws.readyState === 1) {
+				ws.send(JSON.stringify({
+					type: 'ldap_tunnel',
+					payload: { conn_id: connId, close: true }
+				}));
+			}
+		});
+		sock.on('error', () => { sock.destroy(); });
+	}
+	sock.write(data);
+}
+
+// Drop every relay socket for an agent (on WSS disconnect).
+function cleanup(agentId) {
+	const conns = relays.get(agentId);
+	if (conns) {
+		for (const sock of conns.values()) sock.destroy();
+		relays.delete(agentId);
+	}
+}
+
+module.exports = { handleTunnel, cleanup };