Jobs: Bewerbungssystem für Social-Media-Manager/in

Backend:
- job_applications + job_application_docs Tabellen in DB
- luna_trial_until Spalte in users (Migration)
- routes/jobs.py: POST /apply (FormData + Datei-Upload, max 3×10MB),
  GET /my-application, GET /luna-trial-status
- Admin: GET/PATCH /admin/applications, GET /admin/applications/{id}/docs/{doc_id}
- Bei Bewerbung: 14-Tage Luna-Probezugang automatisch aktiviert
- Bei Annahme: is_social_media=1 + Gründer-Status gesetzt
- Status-Mails (pending/reviewing/accepted/rejected) via email_html-Template
- auth.py: require_social_media prüft auch luna_trial_until

Frontend:
- pages/jobs.js: Stellenausschreibung + Bewerbungsformular
  (Name, E-Mail, Hund, Social-Handle, Motivation, Datei-Upload)
- Luna-Probezugang Teaser mit Countdown wenn aktiv
- Bestehende Bewerbung: Status-Screen statt Formular
- app.js: 'jobs' Seite registriert
- admin.js: neuer Tab 'Bewerbungen' (filtert nach Status,
  Statuswechsel per Dropdown, Detailansicht mit Anhang-Download,
  Admin-Notiz-Feld)
- admin.js: Tab 'Jobs' → 'Scheduler' umbenannt

backend/database.py

@@ -1582,6 +1582,35 @@ def _migrate(conn_factory):
         if 'from_account' not in existing_ol:
             conn.execute("ALTER TABLE outreach_log ADD COLUMN from_account TEXT DEFAULT 'partner'")
 
+        # Job-Bewerbungen + Luna-Probezugang
+        conn.executescript("""
+            CREATE TABLE IF NOT EXISTS job_applications (
+                id           INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id      INTEGER REFERENCES users(id) ON DELETE SET NULL,
+                name         TEXT    NOT NULL,
+                email        TEXT    NOT NULL,
+                dog_name     TEXT,
+                dog_rasse    TEXT,
+                social_handle TEXT,
+                motivation   TEXT    NOT NULL,
+                status       TEXT    NOT NULL DEFAULT 'pending',
+                admin_note   TEXT,
+                created_at   TEXT    NOT NULL DEFAULT (datetime('now')),
+                reviewed_at  TEXT
+            );
+            CREATE INDEX IF NOT EXISTS idx_job_apps_status ON job_applications(status, created_at DESC);
+            CREATE TABLE IF NOT EXISTS job_application_docs (
+                id             INTEGER PRIMARY KEY AUTOINCREMENT,
+                application_id INTEGER NOT NULL REFERENCES job_applications(id) ON DELETE CASCADE,
+                filename       TEXT    NOT NULL,
+                file_path      TEXT    NOT NULL,
+                uploaded_at    TEXT    NOT NULL DEFAULT (datetime('now'))
+            );
+        """)
+        existing_u = [row[1] for row in conn.execute("PRAGMA table_info(users)").fetchall()]
+        if 'luna_trial_until' not in existing_u:
+            conn.execute("ALTER TABLE users ADD COLUMN luna_trial_until TEXT")
+
         # js_exercise_id zu training_exercises — verbindet training_exercises mit exercise_progress
         existing_te = [row[1] for row in conn.execute("PRAGMA table_info(training_exercises)").fetchall()]
         if 'js_exercise_id' not in existing_te: