feat: two-way sync between support tickets and Gitea issues (v0.63.0)

Outbound (already existed one-way: ticket create -> Gitea issue) now
also mirrors status changes: closing/reopening a ticket in the admin
UI closes/reopens the linked Gitea issue, and replies posted from
Epicure (by the ticket owner or an admin) post as a comment on the
issue. Captures and stores the Gitea issue number at creation time
to address these follow-up calls without re-parsing the issue URL.

Inbound: new webhook receiver at /api/webhooks/gitea, verified via
HMAC-SHA256 signature (X-Gitea-Signature) with a configurable
GITEA_WEBHOOK_SECRET site setting, deduped by delivery id the same
way the existing Stripe receiver dedupes events. Handles "issues"
(closed/reopened -> ticket status) and "issue_comment" (created ->
appends to the ticket's comment thread), skipping comments Epicura
already posted itself (matched by Gitea comment id) to avoid loops.

New support_ticket_comments table backs a lightweight conversation
thread on both the user-facing support page and the admin support
manager, each comment tagged by author (user/admin/gitea).

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

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 All notable changes to Epicure are documented here. This file is mirrored in-app at `/changelog` (and in the admin dashboard) via `apps/web/lib/changelog.ts` — update both together.
 
+## 0.63.0 — 2026-07-21 00:15
+
+### Added
+- Support tickets now sync two-way with their linked Gitea issue: closing/reopening the issue in Gitea updates the ticket's status, and comments on either side (Epicure or Gitea) show up in both places. Configure a webhook secret (`GITEA_WEBHOOK_SECRET`) on the Gitea repo's webhook, subscribed to Issues and Issue Comment events, pointed at `/api/webhooks/gitea`.
+
 ## 0.62.0 — 2026-07-20 23:45
 
 ### Added