Repair command behavior and file report reliability

[incredincomp]

Summary

• repaired the production-fragile private formatter dependency in Show File Details with stable shared formatting
• added explicit command outcomes so handled failures, cancellation, empty results, and already-running reports cannot become false success
• repaired report inclusion, bounded time ranges, unknown activity semantics, safe serialization, cancellation, single-flight generation, verified atomic saves, and cleanup
• regenerated and parity-checked production desktop and web bundles

Validation

• terminal suite: 103/103 passed, zero failures, zero skips
• report fixture: 14 total / 6 included / 8 excluded
• focused mutation adequacy: 9/9 implemented cases rejected by focused contracts
• production desktop and web report contracts, dist parity, bundle integrity, chunk verification, and web smoke: passed
• real VS Code 1.129.0 Show File Details host smoke: passed, including selected-file and active-editor fallback
• exact-head Public PR Validation run 29716018434: completed successfully on 4fb7c8945cc6697d1b6bfa098cb280db1d6b15ea

Scope and remaining certification

Windows VS Code Insiders runtime certification remains pending. Remote SSH and Codespaces are environment-certification follow-ups; browser-host report generation is unavailable by contract. Broad certification of all 44 contributed commands and the general 44-case disposable mutation platform are deferred to a separate post-merge public-core testing lane. No release, publication, Marketplace, VSIX, or Explorer Dates Pro change is included.