fix(providers): declare qwen3.8-max video input and keep both deepseek flash ids

Review follow-up on two points.

The qwen3.8-max family reached the modality default table as image-only, so
every config that carries no explicit modalities — the VS Code companion
template, which ships none for any model, plus manually typed model ids and
installs predating the preset entry — silently dropped video input the model
accepts. Declaring video on the family pattern fixes all of those paths at
once instead of widening the companion's duplicate spec, and lines the
default up with the preset, which already declared video for the preview.

Swapping deepseek-v4-flash for the dated snapshot removed a still-live id.
The bare alias answers Singapore's Token Plan endpoint with 403 Unpurchased,
not 404, so it is missing from that plan's entitlement rather than retired,
and it remains a built-in of the DeepSeek, Alibaba standard and IdeaLab
presets. Shipping both ids strands neither region's users and drops the need
to migrate installed model selections.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: yibudak

packages/core/src/core/modalityDefaults.test.ts

@@ -155,15 +155,18 @@ describe('defaultModalities', () => {
       expect(defaultModalities('qwen3.7-max')).toEqual({});
     });
 
-    it('returns image for qwen3.8-max', () => {
+    it('returns image + video for qwen3.8-max', () => {
       const m = defaultModalities('qwen3.8-max');
       expect(m.image).toBe(true);
-      expect(m.video).toBeUndefined();
+      expect(m.video).toBe(true);
+      expect(m.pdf).toBeUndefined();
+      expect(m.audio).toBeUndefined();
     });
 
-    it('returns image for qwen3.8-max-preview (provider-prefixed)', () => {
+    it('returns image + video for qwen3.8-max-preview (provider-prefixed)', () => {
       const m = defaultModalities('bailian-token-plan/qwen3.8-max-preview');
       expect(m.image).toBe(true);
+      expect(m.video).toBe(true);
     });
 
     it('returns image + video for qwen3.6-35b variants', () => {

packages/core/src/core/modalityDefaults.ts

@@ -44,8 +44,8 @@ const MODALITY_PATTERNS: Array<[RegExp, InputModalities]> = [
   [/^qwen3\.5-plus/, { image: true, video: true }],
   [/^qwen3\.6-plus/, { image: true, video: true }],
   [/^qwen3\.7-plus/, { image: true, video: true }],
-  // Qwen Max models (3.8+): image support
-  [/^qwen3\.8-max/, { image: true }],
+  // Qwen Max models (3.8+): image + video support
+  [/^qwen3\.8-max/, { image: true, video: true }],
   [/^coder-model$/, { image: true, video: true }],
 
   // Qwen VL (vision-language) models: image + video

packages/core/src/providers/__tests__/presets/alibaba-token-plan.test.ts

@@ -42,6 +42,7 @@ describe('token plan provider', () => {
       'qwen3.8-max-preview',
       'qwen3.6-flash',
       'deepseek-v4-pro',
+      'deepseek-v4-flash',
       'deepseek-v4-flash-0731',
       'deepseek-v3.2',
       'kimi-k2.7-code',

packages/core/src/providers/presets/alibaba-token-plan.ts

@@ -54,6 +54,12 @@ const TOKEN_PLAN_MODELS: ModelSpec[] = [
     enableThinking: true,
   },
   { id: 'deepseek-v4-pro', contextWindowSize: 1000000 },
+  // Singapore's catalog lists only the dated snapshot; the bare alias answers
+  // there with 403 Unpurchased rather than 404, so it is a per-plan entitlement
+  // gap, not a retired id — it stays a built-in of the DeepSeek, Alibaba
+  // standard and IdeaLab presets. Both ship rather than one replacing the
+  // other, so neither region's users are stranded.
+  { id: 'deepseek-v4-flash', contextWindowSize: 1000000 },
   { id: 'deepseek-v4-flash-0731', contextWindowSize: 1000000 },
   { id: 'deepseek-v3.2', contextWindowSize: 131072 },
   {

packages/vscode-ide-companion/src/services/subscriptionPlanDefinitions.test.ts

@@ -24,6 +24,7 @@ describe('subscription plan definitions', () => {
       'qwen3.8-max-preview',
       'qwen3.6-flash',
       'deepseek-v4-pro',
+      'deepseek-v4-flash',
       'deepseek-v4-flash-0731',
       'deepseek-v3.2',
       'kimi-k2.7-code',
@@ -41,6 +42,15 @@ describe('subscription plan definitions', () => {
       tokenPlan.template.find((model) => model.id === 'deepseek-v4-pro')
         ?.generationConfig,
     ).toEqual({ contextWindowSize: 1000000 });
+    // The companion spec carries no modality metadata for any model, so
+    // qwen3.8-max relies on the core defaultModalities() fallback for video.
+    expect(
+      tokenPlan.template.find((model) => model.id === 'qwen3.8-max')
+        ?.generationConfig,
+    ).toEqual({
+      extra_body: { enable_thinking: true },
+      contextWindowSize: 1000000,
+    });
   });
 
   it('defaults Token Plan to China and supports the Singapore region', () => {

packages/vscode-ide-companion/src/services/subscriptionPlanDefinitions.ts

@@ -127,6 +127,7 @@ const BAILIAN_TOKEN_PLAN_MODELS = [
   },
   { id: 'qwen3.6-flash', contextWindowSize: 1000000, enableThinking: true },
   { id: 'deepseek-v4-pro', contextWindowSize: 1000000 },
+  { id: 'deepseek-v4-flash', contextWindowSize: 1000000 },
   { id: 'deepseek-v4-flash-0731', contextWindowSize: 1000000 },
   { id: 'deepseek-v3.2', contextWindowSize: 131072 },
   { id: 'kimi-k2.7-code', contextWindowSize: 262144, enableThinking: true },