Improve provider UX and DeepSeek fallback handling

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Build: pass | Tests: pass — 68 passed (3 files)

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Build: pass | Tests: pass — Tests  2035 passed (2035)

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Build: pass | Tests: pass — Tests  2035 passed (2035)

src/provider-fallback.test.ts

@@ -108,6 +108,32 @@ describe('parseProviderCapError', () => {
     expect(parsed?.until.getTime()).toBe(now.getTime() + 300 * 1000);
   });
 
+  it('detects DeepSeek insufficient balance as a long cooldown', () => {
+    const now = new Date('2026-04-29T01:00:00Z');
+    const parsed = parseProviderCapError(
+      '{"error":{"code":"insufficient_balance","message":"Balance not enough"}}',
+      now,
+      300,
+    );
+    expect(parsed?.provider).toBe('deepseek');
+    expect(parsed?.until.getTime()).toBe(
+      now.getTime() + 24 * 60 * 60 * 1000,
+    );
+    expect(parsed?.reason).toContain('insufficient_balance');
+  });
+
+  it('detects DeepSeek rate limits with the default cooldown', () => {
+    const now = new Date('2026-04-29T01:00:00Z');
+    const parsed = parseProviderCapError(
+      '{"error":{"code":"rate_limit_exceeded","message":"Too many requests"}}',
+      now,
+      300,
+    );
+    expect(parsed?.provider).toBe('deepseek');
+    expect(parsed?.until.getTime()).toBe(now.getTime() + 300 * 1000);
+    expect(parsed?.reason).toBe('DeepSeek 429 rate limit');
+  });
+
   it('returns null for unrelated errors', () => {
     expect(parseProviderCapError('connection refused')).toBeNull();
     expect(parseProviderCapError('429 Too Many Requests')).toBeNull();

src/telegram-commands.test.ts

@@ -111,7 +111,7 @@ describe('command context', () => {
 });
 
 describe('augmentPickerModels', () => {
-  it('adds deepseek-chat for the DeepSeek picker when catalog only has v4 models', () => {
+  it('adds deepseek-chat for the DeepSeek picker and sorts stable above experimental', () => {
     const models = augmentPickerModels('deepseek', [
       {
         id: 'deepseek-v4-flash',
@@ -140,6 +140,11 @@ describe('augmentPickerModels', () => {
       'deepseek-v4-flash',
       'deepseek-v4-pro',
     ]);
+    expect(models.map((m) => m.name)).toEqual([
+      '✓ DeepSeek Chat',
+      '⚠ DeepSeek V4 Flash',
+      '⚠ DeepSeek V4 Pro',
+    ]);
   });
 
   it('does not duplicate deepseek-chat when it is already present', () => {
@@ -158,6 +163,24 @@ describe('augmentPickerModels', () => {
 
     expect(models).toHaveLength(1);
     expect(models[0]?.id).toBe('deepseek-chat');
+    expect(models[0]?.name).toBe('✓ DeepSeek Chat');
+  });
+
+  it('hides deprecated deepseek-reasoner from the picker', () => {
+    const models = augmentPickerModels('deepseek', [
+      {
+        id: 'deepseek-reasoner',
+        provider: 'deepseek',
+        parent: null,
+        name: 'deepseek-reasoner',
+        context_length: null,
+        pricing_in: null,
+        pricing_out: null,
+        free_tier: false,
+      },
+    ]);
+
+    expect(models.map((m) => m.id)).toEqual(['deepseek-chat']);
   });
 
   it('leaves non-DeepSeek providers unchanged', () => {