feat: implement progressive pagination for Asset Browser model assets (#8212)

## Summary

Implements progressive pagination for model assets - returns the first
batch immediately while loading remaining batches in the background.

## Changes

### Store (`assetsStore.ts`)
- Adds `ModelPaginationState` tracking (assets Map, offset, hasMore,
loading, error)
- `updateModelsForKey()` returns first batch, then calls
`loadRemainingBatches()` to fetch the rest
- Accessor functions `getAssets(key)`, `isModelLoading(key)` replace
direct Map access

### API (`assetService.ts`)
- Adds `PaginationOptions` interface (`{ limit?, offset? }`)

### Components
- `AssetBrowserModal.vue` uses new accessor API

### Tests
- Updated mocks for new accessor pattern

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8212-feat-implement-progressive-pagination-for-Asset-Browser-model-assets-2ef6d73d36508157af04d1264780997e)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Amp <amp@ampcode.com>

src/renderer/extensions/vueNodes/widgets/composables/useAssetWidgetData.desktop.test.ts

@@ -12,9 +12,9 @@ const mockGetCategoryForNodeType = vi.fn()
 
 vi.mock('@/stores/assetsStore', () => ({
   useAssetsStore: () => ({
-    modelAssetsByNodeType: new Map(),
-    modelLoadingByNodeType: new Map(),
-    modelErrorByNodeType: new Map(),
+    getAssets: () => [],
+    isModelLoading: () => false,
+    getError: () => undefined,
     updateModelsForNodeType: mockUpdateModelsForNodeType
   })
 }))

src/renderer/extensions/vueNodes/widgets/composables/useAssetWidgetData.test.ts

@@ -8,17 +8,17 @@ vi.mock('@/platform/distribution/types', () => ({
   isCloud: true
 }))
 
-const mockModelAssetsByNodeType = new Map<string, AssetItem[]>()
-const mockModelLoadingByNodeType = new Map<string, boolean>()
-const mockModelErrorByNodeType = new Map<string, Error | null>()
+const mockAssetsByKey = new Map<string, AssetItem[]>()
+const mockLoadingByKey = new Map<string, boolean>()
+const mockErrorByKey = new Map<string, Error | undefined>()
 const mockUpdateModelsForNodeType = vi.fn()
 const mockGetCategoryForNodeType = vi.fn()
 
 vi.mock('@/stores/assetsStore', () => ({
   useAssetsStore: () => ({
-    modelAssetsByNodeType: mockModelAssetsByNodeType,
-    modelLoadingByNodeType: mockModelLoadingByNodeType,
-    modelErrorByNodeType: mockModelErrorByNodeType,
+    getAssets: (key: string) => mockAssetsByKey.get(key) ?? [],
+    isModelLoading: (key: string) => mockLoadingByKey.get(key) ?? false,
+    getError: (key: string) => mockErrorByKey.get(key),
     updateModelsForNodeType: mockUpdateModelsForNodeType
   })
 }))
@@ -32,9 +32,9 @@ vi.mock('@/stores/modelToNodeStore', () => ({
 describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
   beforeEach(() => {
     vi.clearAllMocks()
-    mockModelAssetsByNodeType.clear()
-    mockModelLoadingByNodeType.clear()
-    mockModelErrorByNodeType.clear()
+    mockAssetsByKey.clear()
+    mockLoadingByKey.clear()
+    mockErrorByKey.clear()
     mockGetCategoryForNodeType.mockReturnValue(undefined)
 
     mockUpdateModelsForNodeType.mockImplementation(
@@ -76,8 +76,8 @@ describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
 
     mockUpdateModelsForNodeType.mockImplementation(
       async (_nodeType: string): Promise<AssetItem[]> => {
-        mockModelAssetsByNodeType.set(_nodeType, mockAssets)
-        mockModelLoadingByNodeType.set(_nodeType, false)
+        mockAssetsByKey.set(_nodeType, mockAssets)
+        mockLoadingByKey.set(_nodeType, false)
         return mockAssets
       }
     )
@@ -108,9 +108,9 @@ describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
 
     mockUpdateModelsForNodeType.mockImplementation(
       async (_nodeType: string): Promise<AssetItem[]> => {
-        mockModelErrorByNodeType.set(_nodeType, mockError)
-        mockModelAssetsByNodeType.set(_nodeType, [])
-        mockModelLoadingByNodeType.set(_nodeType, false)
+        mockErrorByKey.set(_nodeType, mockError)
+        mockAssetsByKey.set(_nodeType, [])
+        mockLoadingByKey.set(_nodeType, false)
         return []
       }
     )
@@ -130,8 +130,8 @@ describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
 
     mockUpdateModelsForNodeType.mockImplementation(
       async (_nodeType: string): Promise<AssetItem[]> => {
-        mockModelAssetsByNodeType.set(_nodeType, [])
-        mockModelLoadingByNodeType.set(_nodeType, false)
+        mockAssetsByKey.set(_nodeType, [])
+        mockLoadingByKey.set(_nodeType, false)
         return []
       }
     )
@@ -154,8 +154,8 @@ describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
       mockGetCategoryForNodeType.mockReturnValue('checkpoints')
       mockUpdateModelsForNodeType.mockImplementation(
         async (_nodeType: string): Promise<AssetItem[]> => {
-          mockModelAssetsByNodeType.set(_nodeType, mockAssets)
-          mockModelLoadingByNodeType.set(_nodeType, false)
+          mockAssetsByKey.set(_nodeType, mockAssets)
+          mockLoadingByKey.set(_nodeType, false)
           return mockAssets
         }
       )
@@ -182,8 +182,8 @@ describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
       mockGetCategoryForNodeType.mockReturnValue('loras')
       mockUpdateModelsForNodeType.mockImplementation(
         async (_nodeType: string): Promise<AssetItem[]> => {
-          mockModelAssetsByNodeType.set(_nodeType, mockAssets)
-          mockModelLoadingByNodeType.set(_nodeType, false)
+          mockAssetsByKey.set(_nodeType, mockAssets)
+          mockLoadingByKey.set(_nodeType, false)
           return mockAssets
         }
       )
@@ -209,8 +209,8 @@ describe('useAssetWidgetData (cloud mode, isCloud=true)', () => {
       mockGetCategoryForNodeType.mockReturnValue('checkpoints')
       mockUpdateModelsForNodeType.mockImplementation(
         async (_nodeType: string): Promise<AssetItem[]> => {
-          mockModelAssetsByNodeType.set(_nodeType, mockAssets)
-          mockModelLoadingByNodeType.set(_nodeType, false)
+          mockAssetsByKey.set(_nodeType, mockAssets)
+          mockLoadingByKey.set(_nodeType, false)
           return mockAssets
         }
       )

src/renderer/extensions/vueNodes/widgets/composables/useAssetWidgetData.ts

@@ -34,23 +34,17 @@ export function useAssetWidgetData(
 
     const assets = computed<AssetItem[]>(() => {
       const resolvedType = toValue(nodeType)
-      return resolvedType
-        ? (assetsStore.modelAssetsByNodeType.get(resolvedType) ?? [])
-        : []
+      return resolvedType ? (assetsStore.getAssets(resolvedType) ?? []) : []
     })
 
     const isLoading = computed(() => {
       const resolvedType = toValue(nodeType)
-      return resolvedType
-        ? (assetsStore.modelLoadingByNodeType.get(resolvedType) ?? false)
-        : false
+      return resolvedType ? assetsStore.isModelLoading(resolvedType) : false
     })
 
     const error = computed<Error | null>(() => {
       const resolvedType = toValue(nodeType)
-      return resolvedType
-        ? (assetsStore.modelErrorByNodeType.get(resolvedType) ?? null)
-        : null
+      return resolvedType ? (assetsStore.getError(resolvedType) ?? null) : null
     })
 
     const dropdownItems = computed<DropdownItem[]>(() => {
@@ -71,7 +65,8 @@ export function useAssetWidgetData(
           return
         }
 
-        const hasData = assetsStore.modelAssetsByNodeType.has(currentNodeType)
+        const existingAssets = assetsStore.getAssets(currentNodeType) ?? []
+        const hasData = existingAssets.length > 0
 
         if (!hasData) {
           await assetsStore.updateModelsForNodeType(currentNodeType)