Fix security and correctness issues found in full-codebase audit

- Restrict meetingPassword field so it isn't leaked via the public REST/GraphQL API
- Fix booking slot computation to use Europe/Berlin time instead of the server's UTC clock
- Reset email verification when a customer changes their email address
- Fix ICS calendar injection via unescaped carriage returns in event descriptions
- Bind WebRTC meeting kicks to a persistent client id so they survive a rejoin
- Move the meeting signaling token out of the WebSocket query string into the first message
- Prevent duplicate signaling connections from leaking when the same participant reconnects
- Use the rightmost X-Forwarded-For entry for rate limiting (single trusted reverse proxy)
- Use constant-time comparison for the cron endpoint's bearer token
- Remove SVG from allowed Media upload types (stored-XSS risk, unused anyway)
- Add baseline security headers and a CSP to next.config.ts
- Fix CI/CD script injection via unsanitized git ref names in release.yml

.gitea/workflows/ci.yml

@@ -23,6 +23,7 @@ jobs:
       DATABASE_URI: postgresql://ci:ci@localhost:5432/ci
       PAYLOAD_SECRET: ci-only-not-a-real-secret
       MEETING_SESSION_SECRET: ci-only-not-a-real-secret
+      ANALYTICS_SALT_SECRET: ci-only-not-a-real-secret
       CRON_SECRET: ci-only-not-a-real-secret
       NEXT_PUBLIC_SERVER_URL: http://localhost:3000
     steps: