fix(modules): case-insensitive module ref lookup

Catalog stores lowercase paths (e.g. modules/keyvault) but .bicep files
may use camelCase (e.g. modules/keyVault). Make get_module_by_ref
case-insensitive so completions work regardless of casing.

ilsp/bicep_lsp/modules.py

@@ -129,9 +129,11 @@ class BicepModuleCatalog:
 
         Matches both new-style ('modules/appservice', 'util/types') and old-style
         bare names ('appservice') so completions work regardless of module version.
+        Case-insensitive to handle catalog lowercase vs. camelCase in .bicep files.
         """
+        ref_lower = ref_path.lower()
         for mod in cls._modules:
-            if mod["ref_path"] == ref_path or mod["name"] == ref_path:
+            if mod["ref_path"].lower() == ref_lower or mod["name"].lower() == ref_lower:
                 return mod
         return None