feat: added French support

src/util/messageFilter/UserMessageFilter.test.ts

@@ -111,6 +111,17 @@ describe('processUserMessage slash commands', () => {
     expect(result.pseudoAssistantResponse).toContain('welcome_local_llm-zh_cn.md');
   });
 
+  it('uses the localized welcome asset when fr-FR is selected', async () => {
+    configState.set('general.language', 'fr_fr');
+    configState.set('general.llm_provider', 'local_browser');
+
+    const result = await processUserMessage('/welcome');
+
+    expect(fetch).toHaveBeenCalledWith(expect.stringContaining('chat/welcome_local_llm-fr_fr.md'));
+    expect(result.metadata).toMatchObject({ command: 'welcome', variant: 'local' });
+    expect(result.pseudoAssistantResponse).toContain('welcome_local_llm-fr_fr.md');
+  });
+
   it('falls back to a localized welcome string when welcome markdown fetch fails', async () => {
     configState.set('general.language', 'zh_cn');
     configState.set('general.llm_provider', 'local_browser');
@@ -170,6 +181,19 @@ describe('processUserMessage slash commands', () => {
     expect(message?.content).toContain('welcome_local_llm-zh_cn.md');
   });
 
+  it('uses localized welcome assets for addWelcomeMessage under auto + French locale', async () => {
+    configState.set('general.language', 'auto');
+    vi.stubGlobal('navigator', {
+      languages: ['fr-FR', 'en-US'],
+      language: 'fr-FR',
+    });
+
+    const message = await addWelcomeMessage();
+
+    expect(fetch).toHaveBeenCalledWith(expect.stringContaining('chat/welcome_local_llm-fr_fr.md'));
+    expect(message?.content).toContain('welcome_local_llm-fr_fr.md');
+  });
+
   it('fetches the localized help guide for /help under zh-CN', async () => {
     configState.set('general.language', 'zh_cn');
 
@@ -185,6 +209,15 @@ describe('processUserMessage slash commands', () => {
     expect(result.pseudoAssistantResponse).toContain('chat/help-zh_cn.md');
   });
 
+  it('fetches the localized help guide for /help under fr-FR', async () => {
+    configState.set('general.language', 'fr_fr');
+
+    const result = await processUserMessage('/help');
+
+    expect(fetch).toHaveBeenCalledWith(expect.stringContaining('chat/help-fr_fr.md'));
+    expect(result.pseudoAssistantResponse).toContain('chat/help-fr_fr.md');
+  });
+
   it('falls back to the English help guide when the localized file is missing', async () => {
     configState.set('general.language', 'zh_cn');
     vi.stubGlobal('fetch', vi.fn(async (input: string | URL | Request) => {
@@ -223,6 +256,15 @@ describe('processUserMessage slash commands', () => {
     expect(result.pseudoAssistantResponse).toContain('chat/hotkeys.md');
   });
 
+  it('fetches the localized hotkeys guide for /hotkeys under fr-FR', async () => {
+    configState.set('general.language', 'fr_fr');
+
+    const result = await processUserMessage('/hotkeys');
+
+    expect(fetch).toHaveBeenCalledWith(expect.stringContaining('chat/hotkeys-fr_fr.md'));
+    expect(result.pseudoAssistantResponse).toContain('chat/hotkeys-fr_fr.md');
+  });
+
   it('fetches the localized hotkeys guide for /hotkeys under zh-CN', async () => {
     configState.set('general.language', 'zh_cn');