feat: YAML LSP (/yaml endpoint) + IAC source catalog enrichment

- Add yaml-language-server (Node.js) to Dockerfile stage 3
- Add YAML_LSP_PORT=2090 env var (Dockerfile + ilsp.nomad)
- Start yaml-language-server in background thread (_serve_yaml_lsp)
- Expose /yaml WebSocket endpoint (same WS→TCP proxy as /python and /bicep)
- Load iac_source_catalog.json alongside bicep_modules_catalog.json
- Enrich param_completion_items() with descriptions + required flag from IAC source
  - Required params sorted first (sortText 0_lru_param_0_...) and marked with *
  - detail field shows * prefix for required params
- Update /health to report iac_source_modules + yaml_lsp fields
- Rewrite EDITOR_SETUP.md: WebSocket URLs, YAML schemas config for all editors
  (Helix, Neovim, PyCharm, VS Code) with azure-pipelines + gitea actions schemas
- All 35 tests pass

ilsp/server.py

@@ -29,6 +29,7 @@ logger = logging.getLogger(__name__)
 
 PYTHON_LSP_PORT = int(os.getenv("PYTHON_LSP_PORT", "2087"))
 BICEP_LSP_PORT  = int(os.getenv("BICEP_LSP_PORT",  "2088"))
+YAML_LSP_PORT   = int(os.getenv("YAML_LSP_PORT",   "2090"))
 HTTP_PORT       = int(os.getenv("HTTP_PORT", "8000"))
 
 _CHUNK = 65536
@@ -45,6 +46,20 @@ def _serve_python_lsp(port: int) -> None:
         logger.warning("pylsp exited (code %s) — restarting", proc.returncode)
 
 
+def _serve_yaml_lsp(port: int) -> None:
+    """Start yaml-language-server in TCP socket mode; restart on unexpected exit."""
+    import shutil
+    yaml_ls = shutil.which("yaml-language-server")
+    if not yaml_ls:
+        logger.warning("yaml-language-server not found — /yaml completions disabled")
+        return
+    while True:
+        proc = subprocess.Popen([yaml_ls, f"--socket={port}"])
+        logger.info("yaml-language-server listening on localhost:%d  PID=%d", port, proc.pid)
+        proc.wait()
+        logger.warning("yaml-language-server exited (code %s) — restarting", proc.returncode)
+
+
 async def _pipe(reader: asyncio.StreamReader, writer) -> None:
     """Pipe bytes from reader to writer until EOF."""
     try:
@@ -109,10 +124,13 @@ async def _build_app() -> web.Application:
     app = web.Application()
 
     async def health(_: web.Request) -> web.Response:
+        import shutil
         return web.json_response({
             "status": "ok",
             "pypi_packages": len(PypiCatalog._packages),
             "bicep_modules": len(BicepModuleCatalog._modules),
+            "iac_source_modules": len(BicepModuleCatalog._iac),
+            "yaml_lsp": bool(shutil.which("yaml-language-server")),
         })
 
     async def reload(_: web.Request) -> web.Response:
@@ -132,10 +150,14 @@ async def _build_app() -> web.Application:
     async def bicep_ws(request: web.Request) -> web.WebSocketResponse:
         return await _ws_proxy(request, "127.0.0.1", BICEP_LSP_PORT)
 
+    async def yaml_ws(request: web.Request) -> web.WebSocketResponse:
+        return await _ws_proxy(request, "127.0.0.1", YAML_LSP_PORT)
+
     app.router.add_get("/health", health)
     app.router.add_post("/reload", reload)
     app.router.add_get("/python", python_ws)
     app.router.add_get("/bicep", bicep_ws)
+    app.router.add_get("/yaml", yaml_ws)
     return app
 
 
@@ -152,13 +174,17 @@ async def main_async() -> None:
     # LSP servers run internally on localhost — not exposed outside the container
     threading.Thread(target=_serve_python_lsp, args=(PYTHON_LSP_PORT,), daemon=True).start()
     threading.Thread(target=serve_bicep, args=(BICEP_LSP_PORT,), daemon=True).start()
+    threading.Thread(target=_serve_yaml_lsp, args=(YAML_LSP_PORT,), daemon=True).start()
 
     app = await _build_app()
     runner = web.AppRunner(app)
     await runner.setup()
     site = web.TCPSite(runner, "0.0.0.0", HTTP_PORT)
     await site.start()
-    logger.info("iLSP HTTP on http://0.0.0.0:%d  (ws://.../python  ws://.../bicep)", HTTP_PORT)
+    logger.info(
+        "iLSP HTTP on http://0.0.0.0:%d  (ws://.../python  ws://.../bicep  ws://.../yaml)",
+        HTTP_PORT,
+    )
 
     await asyncio.Event().wait()