FN-6162: keep mobile workflow editor full screen

Keep the mobile workflow editor stage from stretching the canvas wrapper and shrinking the full-screen view.

- adjust the mobile editor-stage canvas wrapper flex rule to avoid consuming the full stage height
- extend the WorkflowNodeEditor mobile CSS contract test to lock the updated flex behavior

Files changed:
 packages/dashboard/app/components/WorkflowNodeEditor.css                | 2 +-
 .../dashboard/app/components/__tests__/WorkflowNodeEditor.css.test.ts   | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

Fusion-Task-Id: FN-6162

Fusion-Task-Lineage: b09d3317-cf22-4fbf-a732-9f4829c1cfd8

packages/dashboard/app/components/WorkflowNodeEditor.css

@@ -1383,7 +1383,7 @@
 
   .wf-editor-body--editor-stage .wf-editor-canvas-wrap {
     display: flex;
-    flex: 1 1 auto;
+    flex: 0 1 auto;
     width: 100%;
     min-width: 0;
     min-height: 0;

packages/dashboard/app/components/__tests__/WorkflowNodeEditor.css.test.ts

@@ -133,6 +133,7 @@ describe("WorkflowNodeEditor mobile CSS contract", () => {
     expect(editorBodyRule).toMatch(/overflow-x\s*:\s*hidden\s*;/);
 
     const editorStageWrapRule = findRule(mobileBlocks, /\.wf-editor-body--editor-stage \.wf-editor-canvas-wrap\s*\{[^}]*\}/);
+    expect(editorStageWrapRule).toMatch(/flex\s*:\s*0 1 auto\s*;/);
     expect(editorStageWrapRule).toMatch(/width\s*:\s*100%\s*;/);
     expect(editorStageWrapRule).toMatch(/min-width\s*:\s*0\s*;/);
     expect(editorStageWrapRule).toMatch(/overflow\s*:\s*hidden\s*;/);