feat(lsp): warn on undeclared block templates and addresses

Add diagnostics that warn when a literal NX command argument names a block
template or address that no loaded .def file declares (diagnostic codes
unknown-block-template and unknown-address). Names computed at runtime
(e.g. $var or "CYCLE_$x") are not checked, and kinds whose .def file is
not loaded are skipped.

The server now recomputes and refreshes diagnostics when .def documents
change (clears cached diagnostics and requests a workspace diagnostic
refresh if the client supports it). Tests cover positive, negative and
invalidated-cache cases.

server/tests/python_tests/test_def_flow.py

@@ -180,3 +180,44 @@ def test_derived_names_are_not_renamed(tmp_path, monkeypatch):
         text_document=lsp.TextDocumentIdentifier(uri=caller.as_uri()), position=_position("absolute_mode")
     )
     assert lsp_server.prepare_rename(params) is None
+
+
+def _warnings(server, tmp_path: Path, source: str):
+    uri = (tmp_path / "check.tcl").as_uri()
+    server.workspace.put_text_document(lsp.TextDocumentItem(uri=uri, language_id="tcl", version=1, text=source))
+    diagnostics = server.lint(server.workspace.get_text_document(uri))
+    return [
+        (diagnostic.code, diagnostic.message, diagnostic.range.start.line, diagnostic.range.start.character, diagnostic.range.end.character)
+        for diagnostic in diagnostics
+        if diagnostic.code in {"unknown-block-template", "unknown-address"}
+    ]
+
+
+def test_unknown_template_and_address_are_warned(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    source = 'proc p {} {\n    MOM_do_template stedy_rest\n    MOM_force Once SPOS "SPSO"\n}\n'
+    assert _warnings(server, tmp_path, source) == [
+        ("unknown-block-template", "Block template 'stedy_rest' is not declared in any loaded .def file", 1, 20, 30),
+        ("unknown-address", "Address 'SPSO' is not declared in any loaded .def file", 2, 25, 29),
+    ]
+
+
+def test_known_and_dynamic_names_are_not_warned(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    source = 'MOM_do_template steady_rest CREATE\nMOM_do_template $name\nMOM_do_template "CYCLE_$x"\nMOM_force Once SPOS\n'
+    assert _warnings(server, tmp_path, source) == []
+
+
+def test_no_warnings_without_loaded_def_files(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    server.def_documents = {}
+    assert _warnings(server, tmp_path, "MOM_do_template stedy_rest\n") == []
+
+
+def test_def_change_invalidates_cached_diagnostics(tmp_path, monkeypatch):
+    server, caller = _project(tmp_path, monkeypatch)
+    server.compute_diagnostics(server.workspace.get_text_document(caller.as_uri()))
+    assert server.diagnostic_snapshot(caller.as_uri()) is not None
+    (tmp_path / "service" / "service.def").write_text(DEF.replace("absolute_mode", "incremental_mode"), encoding="utf-8")
+    server.refresh_def_symbols([tmp_path])
+    assert server.diagnostic_snapshot(caller.as_uri()) is None