Migrate CLAUDE.md from static files to living Hexframe tile system

## Problem: Static Context vs. Living Systems

The current CLAUDE.md tries to encode all project context statically in a text file. This creates several issues:

1. **Static vs. Living Context**: The workflow information becomes stale because it lives in files that need manual updates
2. **Information Overload**: Claude gets a massive dump of context upfront, much of which may not be relevant to the specific task
3. **No Progressive Disclosure**: There's no way for Claude to explore context depth based on what it actually needs
4. **Maintenance Burden**: Every time the project evolves, CLAUDE.md needs manual updates

## Solution: CLAUDE System in Hexframe Tiles

Replace static CLAUDE.md instructions with a minimal file that points to a living "CLAUDE system" in Hexframe tiles.

### Vision: Two-Step Progressive Context

**NEWCLAUDE.md should contain:**
- Minimal boilerplate (tone, style, basic instructions)
- **One primary instruction**: "For project context, call the CLAUDE system tile"
- Specific coordinates for the CLAUDE system root tile
- Instructions on how to use preview vs. full descriptions

**The CLAUDE System Tile Hierarchy:**
```
CLAUDE System (Root)
├── 1. Project Overview (preview: "HexFrame mission, current status")
├── 2. Architecture (preview: "Tech stack, domain structure")
├── 3. Current Workflow (preview: "Active milestone, priorities")
├── 4. Development Commands (preview: "Build, test, lint commands")
├── 5. Code Standards (preview: "Rule of 6, SLA principles")
└── 6. Team Culture (preview: "Values, decision-making")
```

**The Two-Step Process:**
1. **Overview Call**: Get tile hierarchy with just titles + previews for quick scanning
2. **Detail Call**: Get full descriptions for only the relevant tiles

## Implementation Requirements

### 1. Add Preview Text Field to Tiles
- Add `preview` field to tile schema
- Display preview on hover in UI
- Update chat preview widget to show preview in closed state by default

### 2. Enhance MCP Tools
- Add field selection argument to MCP tools (title/preview/description/dbId/coordId...)
- Enable selective data fetching based on what Claude needs

### 3. Create CLAUDE System Tiles
- Design and populate the 6-tile CLAUDE system hierarchy
- Migrate current CLAUDE.md content to appropriate tiles
- Ensure previews are concise and informative

### 4. Update CLAUDE.md
- Create NEWCLAUDE.md with minimal instructions
- Replace static content with MCP tool calls
- Test with actual Claude interactions

### 5. Clean Up
- Remove .workflow folder
- Update any references to old system

## Success Criteria

- [ ] CLAUDE.md is minimal (< 50 lines) and points to tiles
- [ ] Claude can get project overview in 1 MCP call
- [ ] Claude can drill down to specific context as needed
- [ ] Tile system stays current without manual CLAUDE.md updates
- [ ] Better developer experience with progressive context discovery

## Benefits

- **Living Documentation**: Context evolves with the project
- **Progressive Disclosure**: Claude gets relevant context, not information overload
- **Better Maintenance**: No need to manually update CLAUDE.md
- **Improved UX**: Preview fields for quick scanning
- **Recursive Demonstration**: Using Hexframe to organize Hexframe's own AI context