Replace silent null returns with proper LSP errors (kota::fail) for
feature requests on closed documents, failed compilations, invalid
positions, and unresolvable hierarchy items. Add client notifications
(window/logMessage) for key failures so integration tests can observe
errors without reading server logs. Expand logging coverage in
compilation pipeline (compile args, compilation phases, worker results).
Improve test infrastructure: conditional log dump on failure, yield-based
workspace fixture with post-test cleanup, named timing constants replacing
hardcoded sleeps, and log message capture/assertion helpers.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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