feat: fallback token admin GET + Private Pages persistantes

1. _require_gitea: fallback token admin pour les GET (orgs, projects, tree, file)
   _require_user_gitea: token OAuth requis pour les write (save, delete)

2. Private Pages: table gitea_private_pages (user_id, owner, repo, title, content)
   API CRUD: GET/POST/PUT/DELETE /api/gitea/projects/{o}/{r}/private-pages
   UI: liste + éditeur dans le workspace Gitea, lien 🔒 Private Pages dans sidebar
   Lié logiquement au projet (owner+repo), conservé entre sessions

app/db.py

@@ -395,6 +395,20 @@ def init_db():
         except sqlite3.OperationalError:
             pass
         conn.commit()
+        # v2.7: Private pages for Gitea workspaces
+        conn.execute("""
+            CREATE TABLE IF NOT EXISTS gitea_private_pages (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id INTEGER NOT NULL REFERENCES users(id),
+                gitea_owner TEXT NOT NULL,
+                gitea_repo TEXT NOT NULL,
+                title TEXT NOT NULL DEFAULT 'Untitled',
+                content TEXT DEFAULT '',
+                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+            )
+        """)
+        conn.commit()
 
 
 @contextmanager