test(vtable): cover filtered updateRecords persistence

[fangsmile]

Summary

• add an exact regression test for updateFilterRules -> updateRecords -> clear filters with syncRecordOperationsToSourceRecords
• add a runnable debug demo that preserves the updated name and modifiedCells field in source records
• document that the production behavior was introduced by Feat/support cell values change #4913 while closing the missing regression coverage

Closes #4794

Test plan

• Verify the regression test fails on pre-fix commit a68f06035 because source Employee 2 remains unchanged
• Run rushx test --runInBand __tests__/data-update/listTable-data-events.test.ts (16 tests passed)
• Run full rushx test --runInBand (80 suites, 388 tests passed)
• Run rushx compile
• Run VTable source ESLint (0 errors; existing warnings only)
• Run rush build --to @visactor/vtable
• Verify the debug demo in Chrome at desktop and narrow viewports
• Pass repository pre-push package tests

Bugserver note

The attempted photo case was removed because both the newest available build (1.0.0.4553) and oldest available build (1.0.0.4350) passed. Bugserver no longer exposes a pre-fix build, so the case could not distinguish the regression and was not valid evidence.

🤖 Generated with Claude Code