Self-hosted → self-hosted migration fails at report stage — Missing required field "policies" for Appwrite\Models\Database is masked as "Unable to connect to the migration source"

### 👟 Reproduction steps 1. Run two self-hosted Appwrite **1.9.6** instances (official Docker images) — a source ("prod") and a destination ("dev"). The source project contains databases/tables, users, and storage. 2. In the source project, create an API key with **all scopes**. 3. On the destination: Console → Project → Settings → Migrations → Create migration → select **Appwrite** as the source. 4. Enter the source endpoint (`https://<source-host>/v1`), the source project ID, and the API key; select resources (any selection that includes databases). 5. The console issues `GET /v1/migrations/appwrite/report`, which returns **400**. ### 👍 Expected behavior - The migration report is generated and the wizard proceeds, **or** - If the source call fails, the response/logs surface the actual error instead of a generic connectivity message. ### 👎 Actual Behavior `GET /v1/migrations/appwrite/report` returns 400 with: ``` Appwrite\Extend\Exception: Unable to connect to the migration source. Please verify your credentials and ensure the source is reachable from this server. Check for network restrictions such as firewalls, IP allowlists, or outbound connectivity limits. at /usr/src/code/src/Appwrite/Platform/Modules/Migrations/Http/Migrations/Appwrite/Report/Get.php:71 ``` ### 🎲 Appwrite version Different version (specify in environment) ### 💻 Operating system Linux ### 🧱 Your Environment ## Diagnostics performed (connectivity and credentials are NOT the problem) All executed from **inside the destination `appwrite` container**, against the source: - DNS resolves the source FQDN correctly; host is pingable. - `curl -sv https://<source>/v1/health` → TLS handshake succeeds (publicly trusted Let's Encrypt certificate, verification OK); with `X-Appwrite-Project` and `X-Appwrite-Key` (all scopes) → **HTTP 200** `{"name":"http","ping":0,"status":"pass"}`. - `curl -s https://<source>/v1/health/version` → **HTTP 200** `{"version":"1.9.6"}`. - PHP cURL inside the container (s…