refactor(aisidebar): restructure project and implement reasoning mode toggle

- Reorganize project structure and file locations
- Add ReasoningController to manage model selection and reasoning mode
- Update design and requirements for reasoning mode toggle
- Implement model switching between Qwen3-4B-Instruct and Qwen3-4B-Thinking models
- Remove deprecated files and consolidate project layout
- Add new steering and specification documentation
- Clean up and remove unnecessary files and directories
- Prepare for enhanced AI sidebar functionality with more flexible model handling

data/conversations/archive_20251026_073517_b1adec2f.json

@@ -0,0 +1,53 @@
+{
+  "id": "archive_20251026_073517_b1adec2f",
+  "title": "",
+  "created_at": "2025-10-26T07:32:38.950851+00:00",
+  "updated_at": "2025-10-26T07:34:22.390388+00:00",
+  "messages": [
+    {
+      "role": "assistant",
+      "content": "New conversation started. Previous conversation archived.",
+      "timestamp": "2025-10-26T07:32:38.955297+00:00"
+    },
+    {
+      "role": "user",
+      "content": "How are you doing today?",
+      "timestamp": "2025-10-26T07:32:45.446826+00:00"
+    },
+    {
+      "role": "assistant",
+      "content": "I'm doing great! 😊 I'm always here to help with whatever you need—whether it's answering questions, brainstorming ideas, or just chatting. How can I assist you today?",
+      "timestamp": "2025-10-26T07:32:53.923968+00:00"
+    },
+    {
+      "role": "user",
+      "content": "What? /think",
+      "timestamp": "2025-10-26T07:33:08.742179+00:00"
+    },
+    {
+      "role": "assistant",
+      "content": "Ah, I see! 😄 You're probably thinking: *\"What? /think\"* — maybe you meant to say **\"What? I think...\"** or **\"What? / think [something]\"**?  \n\nNo worries at all! I'm here to help you clarify. Could you tell me:  \n- What you were trying to say?  \n- Or what you’d like to *think* about? (Like a question, idea, or just a quick thought?)  \n\nJust say the words, and I’ll help you work through it — no pressure, no judgment! 💡  \nWhat’s on your mind? 🌟",
+      "timestamp": "2025-10-26T07:33:18.998440+00:00"
+    },
+    {
+      "role": "user",
+      "content": "Hello there",
+      "timestamp": "2025-10-26T07:33:55.741794+00:00"
+    },
+    {
+      "role": "assistant",
+      "content": "Hello! 😊 So glad you're here—hope your day is bright and full of good vibes. What's on your mind today? I'm all ears! 🌟",
+      "timestamp": "2025-10-26T07:34:04.592844+00:00"
+    },
+    {
+      "role": "user",
+      "content": "Was",
+      "timestamp": "2025-10-26T07:34:12.781334+00:00"
+    },
+    {
+      "role": "assistant",
+      "content": "Ah, \"Was\" — that’s a fun little fragment! 😄  \nIs this part of a sentence you were thinking of? Like:  \n- *\"Was that helpful?\"*  \n- *\"Was this what you meant?\"*  \n- Or just a quick thought in the middle of something?  \n\nNo worries at all — I’m here to help you untangle it! Just say what’s on your mind, and I’ll match you there. 💬✨  \n\nWhat’s the *full* thought behind \"Was\"? 😊",
+      "timestamp": "2025-10-26T07:34:22.390388+00:00"
+    }
+  ]
+}