feat(editor): right-click context menu + reset layout

Two operator-visible features filling concrete gaps the
jai_client editor exposed:

 - Right-click on any step node opens a popup menu at the
   cursor position with three actions:
   * Duplicate — clones the step with a unique id
     (<base>_2, <base>_3, …) and offsets its position so
     the copy is visible next to the original.
   * Disconnect all inputs — keeps every with-field key
     but clears its expression value, so the step still
     declares the same inputs but no longer wires them to
     any upstream step.
   * Delete — removes the step. Any dangling $refs in
     downstream steps become run-time errors; we don't
     silently rewrite their YAML because the surprise
     would be worse than the explicit error.

 - Floating "Reset layout" button on the canvas (next to
   Fit to screen). Wipes the layout sidecar so AutoLayout
   re-runs from scratch and the topological column
   placement is restored. Auto-fits afterwards. Useful
   when manual drags have drifted into spaghetti and the
   operator wants a clean slate without losing the flow.

Implementation:
 - FlowNode gains an `onContextMenu(Offset globalPos)`
   parameter, wired to GestureDetector.onSecondaryTapDown.
 - FlowEditorController.resetLayout() — clears layout,
   re-seeds via AutoLayout, saves sidecar, notifies.
 - The menu uses Flutter's showMenu() at the global
   cursor position for native-feeling positioning.

Version bumped 0.2.2 -> 0.3.0 — first new operator-visible
feature set since the v0.2 WYSIWYG release.

Signed-off-by: flemming-it <sf@flemming.it>

lib/src/editor_controller.dart

@@ -167,6 +167,18 @@ class FlowEditorController extends ChangeNotifier {
     notifyListeners();
   }
 
+  /// Wipe every position in the sidecar and re-run auto-
+  /// layout from scratch. Useful when manual drags have
+  /// drifted into spaghetti and the operator wants a clean
+  /// topological column layout again. The YAML is untouched.
+  void resetLayout() {
+    _layout = AutoLayout.layout(_graph, FlowLayout.empty());
+    if (_activeName != null) {
+      LayoutStore.saveSync(_activeName!, _layout);
+    }
+    notifyListeners();
+  }
+
   /// Apply a graph-side edit (rename step, change `use`,
   /// adjust `with`, add/remove step, add edge). Emits fresh
   /// YAML into the text controller, then bumps the layout to

lib/src/widgets/flow_canvas.dart

@@ -202,10 +202,13 @@ class _FlowCanvasState extends State<FlowCanvas> {
               ),
             ),
           ),
-          // Floating "Fit to screen" button — recenters the
+          // Floating canvas controls — pinned to the viewport
-          // canvas so every node is in view at once. Pinned
+          // bottom-right so they don't drift with pan. Fit re-
-          // to the bottom-right of the viewport rather than
+          // centres on every node; Reset layout wipes the
-          // the canvas surface so it doesn't drift with pan.
+          // sidecar so AutoLayout repositions from scratch
+          // (useful when a flow's manual layout has drifted
+          // into spaghetti and the operator wants a clean
+          // starting point).
           Positioned(
             right: FaiSpace.md,
             bottom: FaiSpace.md,
@@ -213,12 +216,23 @@ class _FlowCanvasState extends State<FlowCanvas> {
               color: theme.colorScheme.surfaceContainer,
               borderRadius: BorderRadius.circular(FaiRadius.sm),
               elevation: 2,
-              child: IconButton(
+              child: Row(
+                mainAxisSize: MainAxisSize.min,
+                children: [
+                  IconButton(
+                    onPressed: _resetLayout,
+                    icon: const Icon(Icons.dashboard_outlined, size: 18),
+                    tooltip: 'Reset layout',
+                    visualDensity: VisualDensity.compact,
+                  ),
+                  IconButton(
                     onPressed: _fitToContent,
                     icon: const Icon(Icons.fit_screen_outlined, size: 18),
                     tooltip: 'Fit to screen',
                     visualDensity: VisualDensity.compact,
                   ),
+                ],
+              ),
             ),
           ),
         ],
@@ -312,6 +326,7 @@ class _FlowCanvasState extends State<FlowCanvas> {
           delta,
           NodeGeometry.heightFor(step.with_.length),
         ),
+        onContextMenu: (globalPos) => _showStepContextMenu(step, globalPos),
       ),
     );
   }
@@ -707,6 +722,137 @@ class _FlowCanvasState extends State<FlowCanvas> {
     }
   }
 
+  // --- Context menu actions ---
+
+  /// Right-click menu on a step node. Duplicate creates a
+  /// sibling with a fresh id, same use + with-fields, placed
+  /// slightly offset so the operator sees both. Delete drops
+  /// the step entirely; any dangling refs in downstream
+  /// steps become run-time errors with clear messages, which
+  /// is by design (silently rewriting downstream YAML would
+  /// be more surprising than the error).
+  Future<void> _showStepContextMenu(FlowStep step, Offset globalPos) async {
+    final theme = Theme.of(context);
+    final overlay =
+        Overlay.of(context).context.findRenderObject() as RenderBox?;
+    if (overlay == null) return;
+    final result = await showMenu<_StepAction>(
+      context: context,
+      position: RelativeRect.fromRect(
+        Rect.fromPoints(globalPos, globalPos),
+        Offset.zero & overlay.size,
+      ),
+      items: [
+        const PopupMenuItem(
+          value: _StepAction.duplicate,
+          child: Row(
+            children: [
+              Icon(Icons.copy_outlined, size: 16),
+              SizedBox(width: 8),
+              Text('Duplicate'),
+            ],
+          ),
+        ),
+        const PopupMenuItem(
+          value: _StepAction.disconnectAll,
+          child: Row(
+            children: [
+              Icon(Icons.link_off, size: 16),
+              SizedBox(width: 8),
+              Text('Disconnect all inputs'),
+            ],
+          ),
+        ),
+        PopupMenuItem(
+          value: _StepAction.delete,
+          child: Row(
+            children: [
+              Icon(
+                Icons.delete_outline,
+                size: 16,
+                color: theme.colorScheme.error,
+              ),
+              const SizedBox(width: 8),
+              Text('Delete', style: TextStyle(color: theme.colorScheme.error)),
+            ],
+          ),
+        ),
+      ],
+    );
+    if (!mounted || result == null) return;
+    switch (result) {
+      case _StepAction.duplicate:
+        _duplicateStep(step);
+      case _StepAction.disconnectAll:
+        _disconnectAll(step);
+      case _StepAction.delete:
+        _deleteStep(step);
+    }
+  }
+
+  void _duplicateStep(FlowStep step) {
+    final graph = widget.controller.graph;
+    final layout = widget.controller.layout;
+    // Generate a unique id: <base>, <base>_2, <base>_3, ...
+    final existingIds = graph.steps.map((s) => s.id).toSet();
+    var i = 2;
+    var newId = '${step.id}_$i';
+    while (existingIds.contains(newId)) {
+      i++;
+      newId = '${step.id}_$i';
+    }
+    widget.controller.applyGraphEdit(
+      graph.withStepAdded(
+        FlowStep(
+          id: newId,
+          use: step.use,
+          with_: Map<String, dynamic>.from(step.with_),
+        ),
+      ),
+    );
+    // Offset the new node's position so it's visible next to
+    // the original instead of stacking on top.
+    final originalPos = layout.positions[step.id];
+    if (originalPos != null) {
+      widget.controller.moveStep(
+        newId,
+        NodePosition(originalPos.x + 40, originalPos.y + 40),
+      );
+    }
+  }
+
+  void _disconnectAll(FlowStep step) {
+    if (step.with_.isEmpty) return;
+    // Keep the with-field keys; just clear their values so
+    // the parameter list survives but no longer wires to any
+    // upstream step.
+    final cleared = {for (final k in step.with_.keys) k: ''};
+    widget.controller.applyGraphEdit(
+      widget.controller.graph.withStepUpdated(
+        step.id,
+        step.copyWith(with_: cleared),
+      ),
+    );
+  }
+
+  void _deleteStep(FlowStep step) {
+    widget.controller.applyGraphEdit(
+      widget.controller.graph.withStepRemoved(step.id),
+    );
+    if (widget.controller.selectedStepId == step.id) {
+      widget.controller.selectStep(null);
+    }
+  }
+
+  void _resetLayout() {
+    widget.controller.resetLayout();
+    // Re-fit once layout settles so the operator sees the
+    // cleaned-up positions immediately.
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (mounted) _fitToContent();
+    });
+  }
+
   // --- Background ---
 
   Widget _grid(ThemeData theme) {
@@ -722,6 +868,8 @@ class _FlowCanvasState extends State<FlowCanvas> {
   }
 }
 
+enum _StepAction { duplicate, disconnectAll, delete }
+
 enum _DraftSourceKind { step, inputsField }
 
 enum _DraftTargetKind { step, outputsField }

lib/src/widgets/flow_node.dart

@@ -67,6 +67,11 @@ class FlowNode extends StatelessWidget {
   final void Function(Offset delta)? onDrag;
   final VoidCallback? onDragEnd;
 
+  /// Right-click handler. Canvas wires this to a popup menu
+  /// at the cursor position (Duplicate / Delete / Disconnect
+  /// inputs etc.). `null` = no context menu offered.
+  final void Function(Offset globalPos)? onContextMenu;
+
   /// Live status from the most recent run, when this node is
   /// a step. Coloured dot in the header so the operator can
   /// glance at the canvas and see what's running.
@@ -84,6 +89,7 @@ class FlowNode extends StatelessWidget {
     this.onTap,
     this.onDrag,
     this.onDragEnd,
+    this.onContextMenu,
   });
 
   @override
@@ -99,6 +105,9 @@ class FlowNode extends StatelessWidget {
         onTap: onTap,
         onPanUpdate: onDrag == null ? null : (d) => onDrag!(d.delta),
         onPanEnd: onDragEnd == null ? null : (_) => onDragEnd!(),
+        onSecondaryTapDown: onContextMenu == null
+            ? null
+            : (details) => onContextMenu!(details.globalPosition),
         child: Material(
           color: theme.colorScheme.surfaceContainerHigh,
           elevation: selected ? 6 : 2,

pubspec.yaml

@@ -1,6 +1,6 @@
 name: fai_studio_flow_editor
 description: Swappable inline YAML editor for F∆I Studio flows.
-version: 0.2.2
+version: 0.3.0
 publish_to: 'none'
 repository: https://git.flemming.ai/fai/studio-flow-editor