docs(ops): resolve act_runner template merge notes (network + Postgres)

Clarify empty container.network for services DNS and DATABASE_URL hostnames;
merge README / YAML / setup doc wording after stash apply.

Co-authored-by: Cursor <cursoragent@cursor.com>

config/gitea-act-runner/README.md

@@ -7,6 +7,6 @@
 
 Deploy with `bash scripts/dev-vm/apply-act-runner-config.sh` from the repo root (LAN). Full procedure: `docs/04-configuration/GITEA_ACT_RUNNER_SETUP.md`.
 
-**Networking:** keep **`container.network` empty** (`""` in YAML). That lets act_runner attach workflow **`services:`** to the same per-job Docker network as the job container. **`network: bridge`** breaks **`postgres`** (and similar) hostnames → Prisma **P1001**.
+**Networking:** keep **`container.network` empty** (`""` in YAML). act_runner attaches workflow **`services:`** to the same per-job Docker network as the job container. **`network: bridge`** isolates the job from service containers → Prisma **P1001** even when **`DATABASE_URL`** uses **`postgres`**.
 
 **CI env:** in workflows with **`services: postgres:`**, set **`DATABASE_URL`** to **`...@postgres:5432/...`** (service id as host), not **`localhost`**.

config/gitea-act-runner/config-5701-standard.yaml

@@ -26,7 +26,8 @@ cache:
   external_server: ""
 
 container:
-  # Same as config-5700-heavy.yaml — keep empty for `services:` support.
+  # Same as config-5700-heavy.yaml — keep `network` empty so workflow `services:`
+  # (e.g. postgres) share DNS with the job container (see heavy template comments).
   network: ""
   privileged: false
   options: "--cpus=2 --memory=4g --pids-limit=512"