Initial commit: Freepik REST API

FastAPI async wrapper for Freepik cloud AI API supporting image generation
(Mystic, Flux Dev/Pro, SeedReam), video generation (Kling, MiniMax, Seedance),
image editing (upscale, relight, style transfer, expand, inpaint), and
utilities (background removal, classifier, audio isolation). Includes async
task tracking with polling, Docker containerization, and Gitea CI/CD workflow.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/services/webhook.py

@@ -0,0 +1,39 @@
+import hashlib
+import hmac
+import logging
+
+from fastapi import APIRouter, Header, HTTPException, Request
+
+from app.config import settings
+from app.services.task_tracker import handle_webhook_completion
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix='/api/v1', tags=['webhooks'])
+
+
+@router.post('/webhooks/task-complete')
+async def webhook_task_complete(
+    request: Request,
+    x_webhook_signature: str | None = Header(None),
+):
+    body = await request.body()
+
+    if settings.webhook_secret:
+        if not x_webhook_signature:
+            raise HTTPException(status_code=401, detail='Missing webhook signature')
+        expected = hmac.new(
+            settings.webhook_secret.encode(),
+            body,
+            hashlib.sha256,
+        ).hexdigest()
+        if not hmac.compare_digest(expected, x_webhook_signature):
+            raise HTTPException(status_code=401, detail='Invalid webhook signature')
+
+    data = await request.json()
+    task_id = data.get('task_id') or data.get('id')
+    if not task_id:
+        raise HTTPException(status_code=400, detail='Missing task_id in webhook payload')
+
+    handle_webhook_completion(str(task_id), data)
+    return {'status': 'ok'}