feat(speaking): i18n keys for AI config section

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/views/lang/cn.json

@@ -792,6 +792,12 @@
   "ssRound": "轮",
   "ssShowReport": "展示学习报告",
   "ssVideoScene": "影片场景",
+  "ssAiConfig": "AI 配置",
+  "ssCustomGreeting": "会话开场白",
+  "ssCustomGreetingHint": "这句话会逐字作为 AI 第一句话，不会再走模型生成",
+  "ssCustomSystemPrompt": "系统提示词 (System Prompt)",
+  "ssCustomSystemPromptPlaceholderHint": "可用占位符: {video_description}",
+  "ssAiConfigDefaultsLoadError": "默认值加载失败，请刷新",
   "ssAdvancedConfig": "高级配置",
   "ssAssistance": "辅助功能",
   "ssShowEnglish": "显示英文",

src/views/lang/en.json

@@ -793,6 +793,12 @@
   "ssRound": "rounds",
   "ssShowReport": "Show Learning Report",
   "ssVideoScene": "Video Scene",
+  "ssAiConfig": "AI Configuration",
+  "ssCustomGreeting": "Opening Greeting",
+  "ssCustomGreetingHint": "This will be the AI's first utterance, verbatim. No LLM call.",
+  "ssCustomSystemPrompt": "System Prompt",
+  "ssCustomSystemPromptPlaceholderHint": "Available placeholder: {video_description}",
+  "ssAiConfigDefaultsLoadError": "Failed to load defaults. Please refresh.",
   "ssAdvancedConfig": "Advanced Settings",
   "ssAssistance": "Assistance",
   "ssShowEnglish": "Show English",

src/views/lang/hk.json

@@ -793,6 +793,12 @@
   "ssRound": "輪",
   "ssShowReport": "展示學習報告",
   "ssVideoScene": "影片場景",
+  "ssAiConfig": "AI 配置",
+  "ssCustomGreeting": "會話開場白",
+  "ssCustomGreetingHint": "這句話會逐字作為 AI 第一句話，不會再走模型生成",
+  "ssCustomSystemPrompt": "系統提示詞 (System Prompt)",
+  "ssCustomSystemPromptPlaceholderHint": "可用佔位符: {video_description}",
+  "ssAiConfigDefaultsLoadError": "默認值載入失敗，請刷新",
   "ssAdvancedConfig": "高級配置",
   "ssAssistance": "輔助功能",
   "ssShowEnglish": "顯示英文",