clice/openspec/changes/improve-semantic-tokens-and-module-highlighting/tasks.md

1. Semantic Token Collection

• 1.1 Audit src/feature/semantic_tokens.cpp against SymbolKind and SymbolModifiers, and add collection paths for the high-value AST-derived kinds/modifiers covered by the spec.
• 1.2 Replace equal-range Conflict collapsing with explicit token precedence and modifier-merging rules, and add focused unit tests for overlap behavior.
• 1.3 Extend token encoding tests to cover newly emitted semantic kinds/modifiers without regressing multiline and UTF-8/UTF-16 behavior.

2. C++20 Module Highlighting

• 2.1 Implement module-name token extraction for named module declarations using existing CompilationUnitRef, directive, and token-buffer APIs.
• 2.2 Implement module-name token extraction for import statements, including partition forms such as Foo:Bar.
• 2.3 Add regression tests for named modules, imports, global module fragments, private fragments, and dotted/partitioned module fixtures.

3. LSP Semantic Token Delivery

• 3.1 Extend server capability advertisement and request routing to support textDocument/semanticTokens/full/delta.
• 3.2 Add per-document semantic token caching with stable resultId handling and full-result fallback for stale delta requests.
• 3.3 Invalidate semantic token caches on document lifecycle changes and trigger semantic token refresh when recompilation changes highlighting for open documents.

4. Validation

• 4.1 Add or expand unit tests for operators, attributes, concepts, bracket-like tokens, and semantic modifiers that are newly emitted.
• 4.2 Add integration coverage for semantic token full and delta requests in the server test suite.
• 4.3 Run the relevant semantic token and module test targets, then fix any fixture or behavior mismatches discovered during verification.