Clean up Helm chart for Python backend

- Remove configmap.yaml (Python uses env vars, not YAML config)
- Remove migration-job.yaml (SQLAlchemy creates tables on startup)
- Rename migrations.enabled to waitForDatabase
- Set readOnlyRootFilesystem: false (Python needs __pycache__)

helm/orchard/values.yaml

@@ -28,7 +28,7 @@ podLabels: {}
 podSecurityContext: {}
 
 securityContext:
-  readOnlyRootFilesystem: true
+  readOnlyRootFilesystem: false  # Python needs to write __pycache__
   runAsNonRoot: true
   runAsUser: 1000
 
@@ -165,12 +165,8 @@ redis:
       enabled: true
       size: 1Gi
 
-# Database migrations
-migrations:
-  enabled: false
-  image:
-    repository: orchard-server
-    tag: ""
+# Wait for database before starting (SQLAlchemy creates tables on startup)
+waitForDatabase: true
 
 global:
   security: