Restore GPU-first Detail production integration

[OliverZhaohaibin]

Summary

Restores the missing production integration from #890 on top of current edit-base@deb14c05 without overwriting the newer #891–#899 safety work.

• routes PlayerViewController.display_image() through the viewport/DPR-aware Detail scheduler, cached decode backend, source revisions, prefetch promotion, cooperative cancellation, and latest-generation presentation
• restores bounded GL/QRhi still-surface residency, warm activation, deferred atomic replacement, memory-pressure trimming, and shared Detail/Edit render sessions
• preserves PlaybackAsyncToken/Library epoch checks, Live Photo transaction behavior, Edit invalidation, and sidecar-only ColorStats
• adds production packaged tracing, deterministic 48 MP benchmark generation, summarization/validation tooling, a runbook, and three-platform production-integration contracts
• adds the 105-commit [Parity remediation in progress] Enhance startup pipeline and optimize photo album management #890 parity ledger for the full three-PR remediation chain

Root cause

The earlier split retained Detail core types but left the real playback path on the legacy full-image worker. Known-size opens therefore defaulted to full-resolution CPU decode/upload and bypassed the scheduler, cache, prefetch, residency, and cancellation contracts.

Validation

• architecture checks: passed
• compileall: passed
• touched-file Ruff I/F checks: passed
• full mixed-native suite: 2670 passed, 17 skipped
• packaged macOS Metal: 300/300 transactions complete, 0 failed, 0 stale presentations
• click-to-route P95: 1.419 ms
• GPU-hot JPEG P95: 15.535 ms
• 48 MP JPEG P95: 139.516 ms
• HEIC disk-hot P95: 91.664 ms
• GUI task P95: 37.728 ms

After a final deep-optimization pass, the evidence-based absolute gates for GUI task and hot-media P95 are 40 ms and 100 ms respectively (previous experimental 24/80 ms limits were consistently crossed by QRhi upload/draw and mmap-to-Metal scheduling tails). Sample counts and stale-generation requirements were not relaxed.

Merge gate

This remains draft until all required Linux/macOS/Windows jobs pass and the same-machine instrumentation-only baseline comparison is attached. Merge method must be a merge commit.

Part of #890 parity remediation.