fix: make Coolify PostgreSQL requirements compatible

LIVE_DEPLOYMENT_RUNBOOK.md

@@ -1,6 +1,6 @@
 # YGIT Controlled Live Deployment Runbook
 
-Version: 1.3
+Version: 1.4
 Status: Ready for Controlled Live Validation
 Owner: YGIT Operations
 
@@ -27,6 +27,7 @@ It does not declare production readiness before real PostgreSQL, Redis, GitHub,
 - Set `YGIT_DEPLOYMENT_CONFIG_VERSION=1.0.0`.
 - Set `KEYCLOAK_POST_LOGOUT_REDIRECT_URI=https://ygit.net`.
 - Store `POSTGRES_USER`, `POSTGRES_PASSWORD`, and `POSTGRES_DB` only in Coolify secret storage.
+- Use the Coolify-compatible required-variable form `${POSTGRES_USER:?}`, `${POSTGRES_PASSWORD:?}`, and `${POSTGRES_DB:?}`; do not append explanatory fallback text after `:?`.
 - Remove any user-defined `COOLIFY_BRANCH` override and allow Coolify to provide plain `main`.
 - Revert provider mode to `disabled` immediately when provider behavior is uncertain.
 - Do not integrate AG-001 during this validation. AG-001 remains reserved for future App Engine work.
@@ -80,6 +81,8 @@ KEYCLOAK_POST_LOGOUT_REDIRECT_URI=https://ygit.net
 
 Coolify must provide `POSTGRES_USER`, `POSTGRES_PASSWORD`, and `POSTGRES_DB` as secrets. The `DATABASE_URL` value must use the same database identity.
 
+Before redeploy, verify both Production and Preview values of `WORKER_PROVIDER_EXECUTION_MODE` are `disabled`.
+
 Confirm the API and worker use the same Git commit and production environment.
 
 ## Phase 3 — Post-Redeploy Disabled-Mode Smoke

backend/tests/test_coolify_production_configuration.py

@@ -29,21 +29,16 @@ def test_hard_coded_postgres_credentials_are_removed() -> None:
     assert "POSTGRES_DB: ygit" not in source
 
 
-def test_postgres_compose_variables_are_required() -> None:
+def test_postgres_required_variables_have_no_literal_fallback() -> None:
     source = compose_text()
 
-    assert (
-        '${POSTGRES_USER:?POSTGRES_USER is required}'
-        in source
-    )
-    assert (
-        '${POSTGRES_PASSWORD:?POSTGRES_PASSWORD is required}'
-        in source
-    )
-    assert (
-        '${POSTGRES_DB:?POSTGRES_DB is required}'
-        in source
-    )
+    for name in (
+        "POSTGRES_USER",
+        "POSTGRES_PASSWORD",
+        "POSTGRES_DB",
+    ):
+        assert f"${{{name}:?}}" in source
+        assert f"${{{name}:?{name} is required}}" not in source
 
 
 def test_postgres_healthcheck_uses_runtime_database_identity() -> None:
@@ -203,3 +198,4 @@ def test_runbook_locks_controlled_redeploy_identity() -> None:
     )
     assert "WORKER_PROVIDER_EXECUTION_MODE=disabled" in source
     assert "Coolify secret storage" in source
+    assert "Coolify-compatible required-variable form" in source

docker-compose.yml

@@ -43,9 +43,9 @@ services:
     image: postgres:16-alpine
     container_name: ygit-postgres
     environment:
-      POSTGRES_USER: "${POSTGRES_USER:?POSTGRES_USER is required}"
-      POSTGRES_PASSWORD: "${POSTGRES_PASSWORD:?POSTGRES_PASSWORD is required}"
-      POSTGRES_DB: "${POSTGRES_DB:?POSTGRES_DB is required}"
+      POSTGRES_USER: "${POSTGRES_USER:?}"
+      POSTGRES_PASSWORD: "${POSTGRES_PASSWORD:?}"
+      POSTGRES_DB: "${POSTGRES_DB:?}"
     volumes:
       - ygit_postgres_data:/var/lib/postgresql/data
     healthcheck: