[datlechin]

Pick of #3848.

Summary

• Same behavior as fix(tabs): keep a table tab's rows until you reload it #3848 on 0.83: no 5 s resign-key eviction, no per-switch row budget, no isEvicted, evict(for:), QueryTab.loadEpoch, discardRowsKeepingMetadata or MemoryPressureAdvisor.
• A tab TablePro wrote to still reloads when shown. ParkedTableLoad, the shared holdsUnsavedWork and the canEditActiveResult busy gate come over as on main.
• Differs from main because 0.83 predates refactor(data-grid)!: rebuild the macOS data grid on one model and native AppKit #3833:
  • 0.83 has no grid models, so no pruneGridDisplayCaches at the switch. Its displayStateCache already prunes itself on insert; that prune now uses GridDisplayCacheBudget instead of the pressure-halved MemoryPressureAdvisor budget.
  • holdsUnsavedWork matches the change manager to the selected tab (0.83 has no changeManagerTabId) and counts an open cell through hasOpenCellOverlay, the check 0.83's refresh plan already used (no isEditingActiveGrid).
  • FindBarView's rowsRevision drops loadEpoch; only eviction moved it.
  • Dropped the stale doc comment on handleWindowDidResignKey.
• Tests adapted to 0.83's types:
  • changedTableWaitsForAnOpenCell opens a real CellOverlayViewer instead of main's DataGridMountedView stub.
  • TableTabRowRetentionTests checks displayStateCache instead of grid model caches; the switching case is a contract test here, since 0.83 has no deferred prune to wait on.
  • rowsAreReadOnlyWhileReplaced checks canEditActiveResult only (0.83 has no gridConfiguration(for:)).
• Changelog fragments kept as 3848.*.md.

Test plan

• verify.sh build: PASS
• verify.sh test: 242 executed, 242 passed, 0 failed, over the 20 suites fix(tabs): keep a table tab's rows until you reload it #3848 touched or that read the changed code (TableTabRowRetentionTests, MainContentCoordinatorLazyLoadTests, CatalogChangeWindowTests, MainContentCoordinatorTabSwitchTests, TableRowsRefreshPlanTests, MaterializedViewRowWriteTests, GridDisplayCacheBudgetTests and others)
• rowsAreReadOnlyWhileReplaced and changedTableWaitsForAnOpenCell assert the two gates release/0.83 lacks (the busy edit gate, the open cell in canAutoLoadTableTab). Not run against the unfixed branch.
• verify.sh lint on the 32 changed Swift files: PASS, 0 violations

Fixes #3841