feat(research): add project detail presentation model

[hubab1]

Summary

• add a closure-injected project-detail model for scoped keyword membership management
• thread every returned project revision through add, remove, and edit operations
• keep ranking and popularity refresh lanes independent for each exact keyword incarnation
• preserve valid pagination while requiring reconciliation when a mutation supersedes an unknown initial page

Correctness

• mutations and provider refreshes check cancellation before starting but publish successful committed returns without a post-commit cancellation lie
• replacement projects and stale completions are generation-checked
• refresh lanes are keyed by full keyword generation, so remove/recreate with the same UUID cannot inherit stale evidence or a stuck spinner
• canceled non-cancellation errors restore loading/refresh state
• continuation availability is hidden whenever reconciliation is required, matching the guarded paging operation
• structured Apple Ads outcomes remain successful evidence even when they carry a reconnect, fallback, or availability issue
• destructive conflicts are surfaced and never retried automatically

Validation

• 10 focused detail-model tests passed
• 437 tests pass at this stack boundary; 445 passed at the current stacked UI head
• signed Debug build passed
• strict deep code-sign verification passed
• all independent-review findings were fixed and the final P1/P2 review was clear
• GitHub Actions is green for the amended head

Review gate

This is a stacked draft on PR #52 / 34b-research-project-list-model. It adds no UI entry point, performs no automatic provider work, and was not launched against the maintainer's live V5 store.

Implementation is independent; no external co-author applies.