refactor(tables): phase 2-5 — selection by array index, checks by row id

Decouple Tables UI selection coordinates from DB position:
- rowIndex semantics shift from row.position to array index across
  selection state, mouse handlers, keyboard nav, paste, scrollIntoView
- checkedRows: Set<number> (position) → Set<string> (rowId), survives
  sort/filter and realtime row inserts
- lastCheckboxRowRef stores rowId; shift-click range resolves to current
  array indices for visual-order ranges
- Drop positionMap/maxPosition derived state in favor of direct rowsRef
  reads
- ExpandedCellPopover anchors via data-row-id (row-id-stable) instead
  of data-row (array index)
- collectRowSnapshots accepts Iterable<TableRowType> directly
- Add bounds-validation effect to clamp anchor/focus when rows.length
  shrinks (sort change, pagination, realtime delete)
- Drop redundant arrayIndex prop on DataRow (rowIndex now equals it)

Server-side position math stays at API boundary only: insertRow,
duplicateRow, shift-Enter append, paste create-batch, undo snapshots.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: waleedlatif1

apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table/cells/expanded-cell-popover.tsx

@@ -78,7 +78,7 @@ export function ExpandedCellPopover({
       return
     }
     setDraftValue(isEditable ? formatValueForInput(target.value, target.column.type) : '')
-    const selector = `[data-table-scroll] [data-row="${target.row.position}"][data-col="${target.colIndex}"]`
+    const selector = `[data-table-scroll] [data-row-id="${target.row.id}"][data-col="${target.colIndex}"]`
     const el = document.querySelector<HTMLElement>(selector)
     if (!el) {
       setRect(null)