Add a new def_flow analysis module that follows .def block template
and address names through local variables and proc parameters, and a
wrapper-table builder to resolve proc arguments that forward .def names.
Derived names are resolved only for hover/definition (not for rename).
Integrate this into the LSP:
- lsp_server: add _word_at and _tcl_def_symbol helpers; fallback to
derived_def_symbol when direct NX-argument navigation fails for hover,
goto-definition and references; return proper ranges for hover.
- lsp_tclserver: cache and expose a def_wrapper_table built from index
def_flows (with cache invalidation on index generation).
Also add unit tests for def_flow and update CHANGELOG to note hover/
definition and completion preview improvements for derived names.
Christoph
5b027a2717