chore(release): public-release readiness fixes for 1.1.18

- CHANGELOG.md now embeds full app-level release notes for submodule bumps.
- .env.example uses explicit CHANGE-ME placeholders instead of realistic-looking defaults.
- config.example comments describe the actual CONF_SECRETS mechanism.
- setup.sh summary no longer prints generated passwords to stdout.
- bootstrap.js fails hard instead of falling back to weak default passwords.

Note: submodule pins will be updated to v1.1.16 after the app PRs merge.

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

config.example/proxy-secrets.js.example

@@ -5,8 +5,8 @@
 // bootstrap writes the OAuth client clientId/clientSecret back into it; this
 // file documents the shape for manual editing / reference.
 //
-// The proxy app reads this via @simpleworkjs/conf (docker-entrypoint.sh
-// symlinks it to /app/conf/secrets.js). Never commit ./config/.
+// The proxy app reads this via @simpleworkjs/conf (docker-entrypoint.sh sets
+// CONF_SECRETS to point at it). Never commit ./config/.
 
 module.exports = {
 	oidc: {