improvement(folders): show the pin glyph on Files rows and pin the deploy contract

Files rows were left without the pin indicator the other two lists gained, so a pinned
file or folder still sorted to the top of the Files page with nothing explaining why.

Adds `lib/api/contracts/folders.test.ts`, which pins the three cases that together ARE
the rolling-deploy contract: an omitted `resourceType` defaults to `workflow` (so a client
predating the field keeps working), a present-but-unrecognized one is rejected rather than
coerced, and every served tree is accepted.

Author: waleedlatif1

apps/sim/app/workspace/[workspaceId]/files/files.tsx

@@ -505,6 +505,7 @@ export function Files() {
         name: {
           icon: <Folder className='size-[14px]' />,
           label: folder.name,
+          pinned: pinnedFolderIds.has(folder.id),
         },
         size: {
           label:
@@ -530,6 +531,7 @@ export function Files() {
           name: {
             icon: <Icon className='size-[14px]' />,
             label: file.name,
+            pinned: pinnedFileIds.has(file.id),
           },
           size: {
             label: formatFileSize(file.size, { includeBytes: true }),
@@ -547,7 +549,7 @@ export function Files() {
     })
 
     return [...folderRows, ...fileRows]
-  }, [visibleFolders, filteredFiles, membersById, folderSizeMap])
+  }, [visibleFolders, filteredFiles, membersById, folderSizeMap, pinnedFolderIds, pinnedFileIds])
 
   const rows: ResourceRow[] = useMemo(() => {
     if (!listRename.editingId) return baseRows

apps/sim/lib/api/contracts/folders.test.ts

@@ -0,0 +1,28 @@
+/**
+ * @vitest-environment node
+ */
+import { describe, expect, it } from 'vitest'
+import { servedFolderResourceTypeSchema } from '@/lib/api/contracts/folders'
+
+/**
+ * These three cases together ARE the rolling-deploy contract for the folder engine, so they
+ * are pinned rather than left implicit in `.default()`.
+ */
+describe('servedFolderResourceTypeSchema', () => {
+  it('defaults an omitted value to workflow, so a client that predates the field still works', () => {
+    expect(servedFolderResourceTypeSchema.parse(undefined)).toBe('workflow')
+  })
+
+  it('rejects a present-but-unrecognized value rather than coercing it to workflow', () => {
+    // Coercing would file a knowledge-base folder into the workflow tree, where the
+    // Knowledge page can never see it again. A 400 is the only safe answer.
+    expect(servedFolderResourceTypeSchema.safeParse('bogus').success).toBe(false)
+    expect(servedFolderResourceTypeSchema.safeParse('').success).toBe(false)
+  })
+
+  it('accepts every tree the engine serves', () => {
+    for (const value of ['workflow', 'file', 'knowledge_base', 'table'] as const) {
+      expect(servedFolderResourceTypeSchema.parse(value)).toBe(value)
+    }
+  })
+})