Feature: Partner-Codes + Gründer-Lizenz-System für Influencer-Kooperationen

- partner_codes Tabelle: Code, Label, max_uses, grants_founder, uses-Counter
- users: is_founder + is_partner Flags (DB-Migration + auth.py SELECT)
- Registrierung: Partner-Code löst Gründer-Lizenz aus (vor User-Referral geprüft)
- API: GET/POST/DELETE /api/admin/partner/codes, POST /api/admin/partner/users/{id}/grant
- API: GET /api/partner/codes/{code}/info (öffentlich, für Registrierungsvalidierung)
- API: GET /api/admin/users/search (Name-Suche für Admin-UI)
- Admin-Tab "Partner & Codes": Code anlegen, Stats, User-Status vergeben
- Registrierungsformular: Einladungscode-Feld mit Live-Validierung
- Settings: Gründer (lila) + Partner (blau) Badge neben Kostenlos/Plus
- SW by-v515, APP_VER 492

backend/routes/auth.py

@@ -78,13 +78,36 @@ async def register(data: RegisterRequest, response: Response, request: Request):
         new_user_id = user["id"]
 
         if data.ref_code:
-            referrer = conn.execute(
-                "SELECT id FROM users WHERE referral_code=? AND id != ?",
-                (data.ref_code.strip().upper(), new_user_id)
+            code_upper = data.ref_code.strip().upper()
+            # Zuerst prüfen ob es ein Partner-Code ist
+            partner = conn.execute(
+                "SELECT id, grants_founder, max_uses, uses FROM partner_codes WHERE code=?",
+                (code_upper,)
             ).fetchone()
-            if referrer:
-                conn.execute("UPDATE users SET referred_by=? WHERE id=?",
-                             (referrer['id'], new_user_id))
+            if partner:
+                # Nur einlösen wenn max_uses nicht erreicht
+                if partner["max_uses"] is None or partner["uses"] < partner["max_uses"]:
+                    conn.execute(
+                        "UPDATE partner_codes SET uses=uses+1 WHERE id=?",
+                        (partner["id"],)
+                    )
+                    updates = {"referred_by": -partner["id"]}
+                    if partner["grants_founder"]:
+                        updates["is_founder"] = 1
+                    set_clause = ", ".join(f"{k}=?" for k in updates)
+                    conn.execute(
+                        f"UPDATE users SET {set_clause} WHERE id=?",
+                        (*updates.values(), new_user_id)
+                    )
+            else:
+                # Fallback: Referral-Code eines anderen Users
+                referrer = conn.execute(
+                    "SELECT id FROM users WHERE referral_code=? AND id != ?",
+                    (code_upper, new_user_id)
+                ).fetchone()
+                if referrer:
+                    conn.execute("UPDATE users SET referred_by=? WHERE id=?",
+                                 (referrer['id'], new_user_id))
 
     token = create_token(user["id"], user["rolle"])
     _set_cookie(response, token)