feat: in-app support form with email + Gitea issue integration (v0.49.0)

Users can now report bugs, suggestions, or questions from a new /support
page. Each submission sends a confirmation email and, when GITEA_URL/
GITEA_TOKEN/GITEA_REPO are configured in admin Settings, opens a labeled
issue on that repo automatically (best-effort — failure doesn't block the
ticket). Admins get a Support section to triage status and retry failed
Gitea issue creation.

New support_tickets table, gitea.ts client, site-settings entries for the
three new secrets, and OpenAPI docs for the two user-facing endpoints.

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

apps/web/messages/fr.json

@@ -84,6 +84,7 @@
     "language": "Langue",
     "notifications": "Notifications",
     "viewProfile": "Voir le profil",
+    "support": "Support",
     "lightMode": "Mode clair",
     "darkMode": "Mode sombre",
     "systemMode": "Système"
@@ -450,6 +451,35 @@
       "description": "Recevez des appels HTTP lorsque des événements se produisent sur votre compte Epicure."
     }
   },
+  "support": {
+    "title": "Support",
+    "subtitle": "Signalez un bug, partagez une suggestion ou posez une question — nous lisons chaque message.",
+    "typeLabel": "Type",
+    "typeBug": "Signalement de bug",
+    "typeSuggestion": "Suggestion",
+    "typeQuestion": "Question",
+    "titleLabel": "Titre",
+    "titlePlaceholder": "Résumé court du problème ou de l'idée",
+    "descriptionLabel": "Description",
+    "descriptionPlaceholder": "Ce qui s'est passé, ce que vous attendiez, et les étapes pour reproduire (si bug) — ou les détails de votre suggestion/question.",
+    "submitButton": "Envoyer",
+    "submitting": "Envoi…",
+    "submitSuccess": "Merci ! Nous avons reçu votre message.",
+    "submitFailed": "Échec de l'envoi — réessayez.",
+    "historyTitle": "Vos tickets",
+    "noTickets": "Vous n'avez encore rien soumis.",
+    "viewIssue": "Voir le ticket",
+    "status": {
+      "open": "Ouvert",
+      "triaged": "Trié",
+      "closed": "Fermé"
+    },
+    "type": {
+      "bug": "Bug",
+      "suggestion": "Suggestion",
+      "question": "Question"
+    }
+  },
   "print": {
     "footer": "Imprimé depuis Epicure",
     "day": "Jour",