fix: yaml stdio per-connection, iac catalog path, makefile port

- yaml-language-server: rewrite to stdio per WebSocket (fixes crash loop)
  vscode-jsonrpc v9 createServerSocketTransport is a TCP client, not server
  now spawns yaml-language-server --stdio per connection via asyncio subprocess

- bicep/modules.py: add /iac_source_catalog.json as first path in _IAC_SOURCE_PATHS
  Dockerfile copies to /iac_source_catalog.json but path wasn't listed

- server.py: remove YAML_LSP_PORT daemon (no longer needed with stdio mode)

- Makefile: add -e HTTP_PORT=$(HEALTH_PORT) to all docker run commands
  server defaulted to :8000 but Makefile exposed :2089 with no override

pipeline_templates_catalog.json

@@ -1,5 +1,5 @@
 {
-  "synced_at": "2026-05-10T13:54:30.009676+00:00",
+  "synced_at": "2026-05-10T14:13:29.433739+00:00",
   "template_count": 48,
   "templates": {
     "tasks/semver.yml@pipeline-templates": {