feat(tcloo): add document-local TclOO completions, signature help and hints

Add conservative, document-local TclOO type inference and tooling so the server
can offer method completions, signature help, and inlay parameter hints for
statically resolvable TclOO receivers (including `new`/`create`, `my`, and
simple return-chains). Also surface class names as completion items and emit
semantic tokens for class declarations/references.

Notable changes:
- New tcloo_* tools: completion, symbols, and argument parsing; integrated into
  on_completion, signature_help, inlay hint generation and semantic token
  highlighting. Completions are returned early when an OO receiver context is
  detected.
- Use a completion-friendly parser fallback when the main AST fails (TclSyntaxError)
  so editing-in-progress code still yields useful completions.
- Add CompletionItemKind.Class to command kinds, exclude class items from the
  poco completion name cache, and include new unit tests for the TclOO helpers.

CHANGELOG.md

@@ -1,5 +1,8 @@
 ## Unreleased
 
+- Add document-local TclOO method completion for `new`/`create` instances, `my`, and statically inferred return chains
+- Suggest TclOO class names as classes and semantically highlight their declarations and calls
+- Show signature help and parameter inlay hints for resolved TclOO methods and constructors, including optional and variadic arguments
 - Add incoming and outgoing call hierarchy for custom TCL procedures and MOM event handlers
 - Add document highlights for procedure and variable occurrences
 - Make completion context-aware and prioritize local, current-file, workspace, and built-in symbols