fix: configure stdio-based MCP servers (penpot, imap)

- Set penpot-mcp restart: "no" for on-demand execution
- Create custom Dockerfile for imap-mcp with python module entrypoint
- Fix IMAP_HOST environment variable naming (was IMAP_SERVER)
- Update .env and docker-compose.yml for IMAP_HOST
- Remove command overrides from imap-mcp and penpot-mcp
- Verify penpot-mcp and imap-mcp work correctly

docker-compose.yml

@@ -248,20 +248,20 @@ services:
       - ops
 
   # IMAP MCP - Email processing
+  # NOTE: This is a stdio-based MCP server, run on-demand by Crush via docker run
   imap-mcp:
     image: kneldevstack-aimiddleware-imap-mcp
     build:
       context: ./vendor/imap-mcp
-      dockerfile: Dockerfile
+      dockerfile: ../../dockerfiles/imap-mcp/Dockerfile
     container_name: kneldevstack-aimiddleware-imap-mcp
-    restart: unless-stopped
+    restart: "no"
     environment:
       - PYTHONUNBUFFERED=1
-      - IMAP_SERVER=${IMAP_SERVER}
+      - IMAP_HOST=${IMAP_HOST}
       - IMAP_PORT=${IMAP_PORT:-993}
       - IMAP_USERNAME=${IMAP_USERNAME}
       - IMAP_PASSWORD=${IMAP_PASSWORD}
-    command: ["uvx", "imap-mcp"]
     profiles:
       - ops
 
@@ -460,13 +460,14 @@ services:
   # ==========================================
 
   # Penpot MCP - Design collaboration platform
+  # NOTE: This is a stdio-based MCP server, run on-demand by Crush via docker run
   penpot-mcp:
     image: kneldevstack-aimiddleware-penpot-mcp
     build:
       context: ./vendor/penpot-mcp
       dockerfile: Dockerfile
     container_name: kneldevstack-aimiddleware-penpot-mcp
-    restart: unless-stopped
+    restart: "no"
     environment:
       - PENPOT_URL=${PENPOT_URL:-https://design.penpot.app}
       - PENPOT_TOKEN=${PENPOT_TOKEN}