refactor(datagrid): migrate callers to TableRows + delete legacy stack

CHANGELOG.md

@@ -22,7 +22,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
-- Introduced TableRows, Row, and Delta value types in TablePro/Models/Query/ as the foundation for the data grid row model rewrite. No callers migrated yet (Phase C.1 of the DataGrid refactor).
+- Replaced RowBuffer / InMemoryRowProvider / RowDataStore with TableRows / TableRowsStore / TableRowsController. Mutations emit Delta events; the controller drives NSTableView via insertRows / removeRows / reloadData(forRowIndexes:). Sort and the display cache moved off the row provider into the data grid coordinator, keyed by Row.id.
+- Routed every TableRows mutation through `mutateActiveTableRows` on MainContentCoordinator so the active ResultSet's snapshot stays in sync with the store. The snapshot now refreshes only when the user switches result sets (saving the outgoing tab, loading the incoming one), so each insert / undo / paste no longer triggers an `@Observable` re-render of the whole editor. Fixes empty cells on Load More and CPU spikes when adding or undoing rows.
+- Undo of a cell edit clears the modified-cell highlight: `DataChangeManager.applyDataUndo` now bumps `reloadVersion` so the data grid rebuilds its visual state cache.
+- Reloading a table tab keeps cached column metadata (defaults, foreign keys, nullability, enum values) when no fresh schema fetch was needed, so the FK arrow and dropdown chevron stay visible across reloads instead of toggling.
 - DataChangeManager extracted a PendingChanges value type that owns cross-collection invariants for cell edits, row insertions, and deletions. DataChangeManager kept undo/redo registration, plugin SQL generation, and the `@Observable` boundary, dropping from ~960 to ~190 lines. The serialization DTO `TabPendingChanges` is renamed to `TabChangeSnapshot` to distinguish it from the live tracker.
 - AnyChangeManager uses ChangeManaging protocol instead of closure-based type erasure, removing all runtime `[Any]` downcasts
 - Row selection state moved from MainContentView @State to GridSelectionState @Observable class, preventing full view tree invalidation on every row click

TablePro/Core/ChangeTracking/AnyChangeManager.swift

@@ -7,6 +7,7 @@ protocol ChangeManaging: AnyObject {
     var reloadVersion: Int { get }
     var canRedo: Bool { get }
     var rowChanges: [RowChange] { get }
+    var insertedRowIndices: Set<Int> { get }
     func isRowDeleted(_ rowIndex: Int) -> Bool
     func recordCellChange(
         rowIndex: Int,
@@ -30,6 +31,7 @@ final class AnyChangeManager {
     var reloadVersion: Int { wrapped.reloadVersion }
     var canRedo: Bool { wrapped.canRedo }
     var rowChanges: [RowChange] { wrapped.rowChanges }
+    var insertedRowIndices: Set<Int> { wrapped.insertedRowIndices }
 
     func isRowDeleted(_ rowIndex: Int) -> Bool {
         wrapped.isRowDeleted(rowIndex)

TablePro/Core/ChangeTracking/DataChangeManager.swift

@@ -17,6 +17,21 @@ struct UndoResult {
     let needsRowRemoval: Bool
     let needsRowRestore: Bool
     let restoreRow: [String?]?
+    let delta: Delta
+
+    init(
+        action: UndoAction,
+        needsRowRemoval: Bool,
+        needsRowRestore: Bool,
+        restoreRow: [String?]?,
+        delta: Delta = .none
+    ) {
+        self.action = action
+        self.needsRowRemoval = needsRowRemoval
+        self.needsRowRestore = needsRowRestore
+        self.restoreRow = restoreRow
+        self.delta = delta
+    }
 }
 
 /// Manager for tracking and applying data changes
@@ -259,7 +274,10 @@ final class DataChangeManager: ChangeManaging {
                 originalDBValue: newValue, newValue: previousValue, originalRow: originalRow
             )
         }
-        lastUndoResult = UndoResult(action: action, needsRowRemoval: false, needsRowRestore: false, restoreRow: nil)
+        lastUndoResult = UndoResult(
+            action: action, needsRowRemoval: false, needsRowRestore: false, restoreRow: nil,
+            delta: .cellChanged(row: rowIndex, column: columnIndex)
+        )
     }
 
     private func applyRowInsertionUndo(rowIndex: Int, action: UndoAction) {
@@ -274,12 +292,14 @@ final class DataChangeManager: ChangeManaging {
         if pending.isRowInserted(rowIndex) {
             _ = pending.undoRowInsertion(rowIndex: rowIndex)
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil
+                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil,
+                delta: .rowsRemoved(IndexSet(integer: rowIndex))
             )
         } else {
             pending.reinsertRow(rowIndex: rowIndex, columns: columns, savedValues: savedValues)
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: savedValues
+                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: savedValues,
+                delta: .rowsInserted(IndexSet(integer: rowIndex))
             )
         }
     }
@@ -292,12 +312,14 @@ final class DataChangeManager: ChangeManaging {
         if pending.isRowDeleted(rowIndex) {
             _ = pending.undoRowDeletion(rowIndex: rowIndex)
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: originalRow
+                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: originalRow,
+                delta: .fullReplace
             )
         } else {
             pending.reapplyRowDeletion(rowIndex: rowIndex, originalRow: originalRow)
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil
+                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil,
+                delta: .fullReplace
             )
         }
     }
@@ -315,14 +337,16 @@ final class DataChangeManager: ChangeManaging {
                 _ = pending.undoRowDeletion(rowIndex: rowIndex)
             }
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: nil
+                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: nil,
+                delta: .fullReplace
             )
         } else {
             for (rowIndex, originalRow) in rows {
                 pending.reapplyRowDeletion(rowIndex: rowIndex, originalRow: originalRow)
             }
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil
+                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil,
+                delta: .fullReplace
             )
         }
     }
@@ -335,15 +359,18 @@ final class DataChangeManager: ChangeManaging {
         }
 
         let firstInserted = rowIndices.first.map { pending.isRowInserted($0) } ?? false
+        let indices = IndexSet(rowIndices)
         if firstInserted {
             _ = pending.undoBatchRowInsertion(rowIndices: rowIndices, columnCount: columns.count)
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil
+                action: action, needsRowRemoval: true, needsRowRestore: false, restoreRow: nil,
+                delta: .rowsRemoved(indices)
             )
         } else {
             pending.reinsertBatch(rowIndices: rowIndices, rowValues: rowValues, columns: columns)
             lastUndoResult = UndoResult(
-                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: nil
+                action: action, needsRowRemoval: false, needsRowRestore: true, restoreRow: nil,
+                delta: .rowsInserted(indices)
             )
         }
     }

TablePro/Core/Plugins/QueryResultExportDataSource.swift

@@ -7,9 +7,6 @@ import Foundation
 import os
 import TableProPluginKit
 
-/// In-memory `PluginExportDataSource` backed by a RowBuffer snapshot.
-/// Allows export plugins (CSV, JSON, SQL, XLSX, MQL) to export query results
-/// without modification to the plugins themselves.
 final class QueryResultExportDataSource: PluginExportDataSource, @unchecked Sendable {
     let databaseTypeId: String
 
@@ -20,14 +17,12 @@ final class QueryResultExportDataSource: PluginExportDataSource, @unchecked Send
 
     private static let logger = Logger(subsystem: "com.TablePro", category: "QueryResultExportDataSource")
 
-    init(rowBuffer: RowBuffer, databaseType: DatabaseType, driver: DatabaseDriver?) {
+    init(tableRows: TableRows, databaseType: DatabaseType, driver: DatabaseDriver?) {
         self.databaseTypeId = databaseType.rawValue
         self.driver = driver
-
-        // Snapshot data at init time for thread safety
-        self.columns = rowBuffer.columns
-        self.columnTypeNames = rowBuffer.columnTypes.map { $0.rawType ?? "" }
-        self.rows = rowBuffer.rows
+        self.columns = tableRows.columns
+        self.columnTypeNames = tableRows.columnTypes.map { $0.rawType ?? "" }
+        self.rows = tableRows.rows.map(\.values)
     }
 
     func streamRows(table: String, databaseName: String) -> AsyncThrowingStream<PluginStreamElement, Error> {

TablePro/Core/Plugins/StreamingQueryExportDataSource.swift

@@ -4,7 +4,7 @@
 //
 //  Streaming export data source for query results.
 //  Re-executes the query and streams rows directly from the database to the export plugin,
-//  bypassing RowBuffer. Allows exporting large result sets without loading all rows into memory.
+//  bypassing in-memory storage. Allows exporting large result sets without loading all rows into memory.
 //
 
 import Foundation

TablePro/Core/SchemaTracking/StructureChangeManager.swift

@@ -887,6 +887,8 @@ final class StructureChangeManager: ChangeManaging {
 
     var rowChanges: [RowChange] { [] }
 
+    var insertedRowIndices: Set<Int> { [] }
+
     func isRowDeleted(_ rowIndex: Int) -> Bool { false }
 
     func recordCellChange(

TablePro/Core/Services/Export/ExportService.swift

@@ -181,15 +181,15 @@ final class ExportService {
     // MARK: - Query Results Export
 
     func exportQueryResults(
-        rowBuffer: RowBuffer,
+        tableRows: TableRows,
         config: ExportConfiguration,
         to url: URL
     ) async throws {
         guard let plugin = PluginManager.shared.exportPlugins[config.formatId] else {
             throw ExportError.formatNotFound(config.formatId)
         }
 
-        let totalRows = rowBuffer.rows.count
+        let totalRows = tableRows.count
         state = ExportState(isExporting: true, totalTables: 1, totalRows: totalRows)
         isCancelled = false
 
@@ -201,7 +201,7 @@ final class ExportService {
         }
 
         let dataSource = QueryResultExportDataSource(
-            rowBuffer: rowBuffer,
+            tableRows: tableRows,
             databaseType: databaseType,
             driver: driver
         )

TablePro/Core/Services/Formatting/CellDisplayFormatter.swift

@@ -3,7 +3,7 @@
 //  TablePro
 //
 //  Pure formatter that transforms raw cell values into display-ready strings.
-//  Used by InMemoryRowProvider's display cache to compute values once per cell.
+//  Used by the data grid coordinator's display cache to compute values once per cell.
 //
 
 import Foundation