docs: add screenshots and update README for v2.2 user profile system

Add visual documentation for the new user profile system and project memory timeline. Update README to reflect v2.2 breaking changes, including deprecation of user-scoped memory additions and introduction of structured user profiles with preferences, patterns, workflows, and skill assessment.

Key documentation updates:
- Add screenshots for project memory timeline and user profile viewer
- Document new profile system configuration options
- Update API documentation with profile endpoints
- Add breaking changes section for v2.2
- Update usage examples to reflect deprecated features
- Add link to User Profile System wiki page

Author: tickernelz

.github/screenshot-project-memory.png

@@ -14,7 +14,7 @@ OpenCode Memory provides AI coding agents with the ability to remember and recal
 - **Dual Memory Scopes**: Separate user-level and project-level memory contexts
 - **Unified Timeline**: Browse memories and prompts together with linking support
 - **Prompt-Memory Linking**: Bidirectional links between prompts and generated memories
-- **User Learning System**: Analyzes user patterns and preferences from conversation history
+- **User Profile System**: Structured learning with preferences, patterns, workflows, and skill assessment
 - **Web Interface**: Full-featured UI for memory management and search
 - **Auto-Capture System**: Intelligent prompt-based memory extraction
 - **Multi-Provider AI**: Support for OpenAI, Anthropic, and OpenAI-compatible APIs
@@ -52,15 +52,25 @@ bun run build
 ### Basic Usage
 
 ```typescript
-memory({ mode: "add", content: "User prefers TypeScript", scope: "user" })
-memory({ mode: "search", query: "coding preferences", scope: "user" })
+memory({ mode: "add", content: "Project uses microservices", scope: "project" })
+memory({ mode: "search", query: "architecture decisions", scope: "project" })
 memory({ mode: "profile" })
 ```
 
+**Note**: User-scoped `add` is deprecated in v2.2+. Use profile system instead.
+
 ### Web Interface
 
 Access at `http://127.0.0.1:4747` to browse memories, view prompt-memory links, and manage your memory database.
 
+**Project Memory Timeline:**
+
+![Project Memory Timeline](.github/screenshot-project-memory.png)
+
+**User Profile Viewer:**
+
+![User Profile Viewer](.github/screenshot-user-profile.png)
+
 ### Configuration
 
 Configuration file: `~/.config/opencode/opencode-mem.jsonc`
@@ -75,10 +85,28 @@ Configuration file: `~/.config/opencode/opencode-mem.jsonc`
   "memoryProvider": "openai-chat",
   "memoryModel": "gpt-4",
   "memoryApiUrl": "https://api.openai.com/v1",
-  "memoryApiKey": "sk-..."
+  "memoryApiKey": "sk-...",
+  "userMemoryAnalysisInterval": 10,
+  "userProfileMaxPreferences": 20,
+  "userProfileMaxPatterns": 15,
+  "userProfileMaxWorkflows": 10,
+  "userProfileConfidenceDecayDays": 30,
+  "userProfileChangelogRetentionCount": 5
 }
 ```
 
+## Breaking Changes (v2.2)
+
+**User-scoped memories deprecated in favor of structured user profiles:**
+
+- Removed: User-scoped `addMemory` (now returns error)
+- Changed: `memory({ mode: "profile" })` returns new structure (preferences/patterns/workflows/skillLevel)
+- Added: 5 new config options for profile management
+- New behavior: User learning creates/updates structured profile instead of individual memories
+- Migration: Existing user memories remain readable but new ones cannot be created
+
+**Migration required**: Update code using `mode: "profile"` to handle new structure.
+
 ## Breaking Changes (v2.0)
 
 **Token-based auto-capture has been replaced with prompt-based system:**
@@ -98,6 +126,7 @@ For detailed documentation, see the [Wiki](https://github.com/tickernelz/opencod
 - [Installation Guide](https://github.com/tickernelz/opencode-mem/wiki/Installation-Guide)
 - [Quick Start](https://github.com/tickernelz/opencode-mem/wiki/Quick-Start)
 - [Configuration Guide](https://github.com/tickernelz/opencode-mem/wiki/Configuration-Guide)
+- [User Profile System](https://github.com/tickernelz/opencode-mem/wiki/User-Profile)
 - [Memory Operations](https://github.com/tickernelz/opencode-mem/wiki/Memory-Operations)
 - [Auto-Capture System](https://github.com/tickernelz/opencode-mem/wiki/Auto-Capture-System)
 - [Web Interface](https://github.com/tickernelz/opencode-mem/wiki/Web-Interface)
@@ -121,18 +150,21 @@ Automatically extracts memories from conversations:
 3. Links memory to source prompt
 4. Skips non-technical conversations
 
-### User Learning System
+### User Profile System
+
+Builds structured user profile from conversation history (default: every 10 prompts):
 
-Analyzes batches of prompts to identify patterns (default: every 10 prompts):
+- **Preferences**: Code style, communication style, tool preferences (with confidence scores)
+- **Patterns**: Recurring topics, problem domains, technical interests (with frequency tracking)
+- **Workflows**: Development sequences, habits, learning style
+- **Skill Level**: Overall and per-domain assessment
 
-- Coding style preferences
-- Communication patterns
-- Tool preferences
-- Skill level indicators
+Profile includes versioning, changelog, and confidence decay mechanism.
 
 ### Web Interface
 
 - Unified timeline of memories and prompts
+- User profile viewer with changelog
 - Visual prompt-memory link indicators
 - Cascade delete for linked items
 - Bulk operations
@@ -144,7 +176,7 @@ Analyzes batches of prompts to identify patterns (default: every 10 prompts):
 ### Memory Tool
 
 ```typescript
-memory({ mode: "add", content: "...", scope: "user|project" })
+memory({ mode: "add", content: "...", scope: "project" })
 memory({ mode: "search", query: "...", scope: "user|project" })
 memory({ mode: "list", scope: "user|project", limit: 10 })
 memory({ mode: "profile" })
@@ -154,14 +186,25 @@ memory({ mode: "auto-capture-stats" })
 memory({ mode: "capture-now" })
 ```
 
+**Note**: `scope: "user"` for `add` mode is deprecated in v2.2+.
+
 ### REST API
 
+**Memory & Prompt Management:**
 - `GET /api/memories?scope=project&includePrompts=true` - List memories/prompts
 - `POST /api/memories` - Create memory
 - `PUT /api/memories/:id` - Update memory
 - `DELETE /api/memories/:id?cascade=true` - Delete memory (and linked prompt)
 - `DELETE /api/prompts/:id?cascade=true` - Delete prompt (and linked memory)
 - `POST /api/search` - Vector search
+
+**User Profile:**
+- `GET /api/profile` - Get user profile
+- `GET /api/profile/changelog?limit=5` - Get profile changelog
+- `GET /api/profile/snapshot/:changelogId` - Get profile snapshot
+- `POST /api/profile/refresh` - Force profile refresh
+
+**Maintenance:**
 - `POST /api/cleanup` - Run cleanup
 - `POST /api/deduplicate` - Run deduplication