feat(card-rewriter): add durable card evolution

[danvitv]

Card Rewriter

• add durable, review-only Card Rewriter jobs with immutable canon, chat, and lorebook provenance
• add Studio controls for enabling automation, selecting its dedicated model, manually running it, and opening proposal history
• evolve only long-term card reference fields and session-scoped injected lorebook entries; retain new-session global lorebook behavior
• add durable model-response diagnostics, claim recovery, configurable writer timeout, and 20k response budgets
• refine validation to use exact anchors, avoid size-based rejection, and keep transient events in Ledger rather than copying them into the card

Review And Reliability

• apply card and lorebook operations atomically after review
• fix review layout duplication, narrow-layout action overflow, and return from review to the originating chat session
• prevent Magic Drawer refreshes from reading Riverpod after its widget is unmounted

Verification

• flutter analyze completed with only six pre-existing info diagnostics in effective_canon_read_repository.dart
• focused Card Rewriter, review, and Magic Drawer suite: 110 tests passed
• full flutter test was run; one Magic Drawer source-contract test failed after the unmount-safety refactor, was updated, and its focused regression suite passed
• git diff --check passed

[danvitv]

Closing: this pull request was opened against the fork by mistake. The change will be proposed to the upstream nightly branch.