feat!: delegation system overhaul and .claude/ shipping (v4.1.0) (#8)

## 🚀 Release v4.1.0 - Major Update

**Breaking changes from v3.5.0**. This release includes the complete v4.0.0 delegation overhaul plus v4.1.0 architecture improvements.

---

## 🎯 v4.0.0: Delegation System Overhaul

**Complete rewrite of the delegation infrastructure with enhanced decision-making and streaming support.**

### New Delegation Features

**Stream-JSON Communication Protocol:**
- Real-time token streaming with `{type: "content", data: "..."}` format
- Progress indicators during delegation execution
- Clean separation: stdout for data, stderr for errors
- Handles tool calls, thinking blocks, and text content

**Enhanced Decision Framework:**
- `/ccs:glm` and `/ccs:kimi` slash commands with auto-enhancement
- `[AUTO ENHANCE]` prompts for better model understanding
- Context-aware task delegation with clear boundaries
- Continuation support: `/ccs:glm:continue` and `/ccs:kimi:continue`

**Robust Error Handling:**
- Graceful degradation when profiles unconfigured
- Clear error messages with actionable fixes
- Signal handling (SIGINT/SIGTERM) for clean child process termination
- Session state recovery on interruption

**Performance & Reliability:**
- Headless mode (`-p` flag) for background execution
- Slash command detection and auto-routing
- Validation system with `DelegationValidator`
- Profile readiness checks in `ccs --version`

### Delegation Components

**New Files:**
- `bin/delegation/delegation-handler.js` - Core delegation orchestrator
- `bin/delegation/stream-processor.js` - Real-time output handling
- `bin/utils/delegation-validator.js` - Profile validation
- `.claude/commands/ccs/*.md` - Slash command definitions
- `.claude/skills/ccs-delegation/` - AI decision framework
- `.claude/agents/ccs-delegator.md` - Proactive delegation agent

**Documentation:**
- Complete delegation workflows with mermaid diagrams
- Troubleshooting guides for common issues
- Headless execution patterns

---

## ✨ v4.1.0: Selective Symlinking Architecture

**Single source of truth for CCS items with automatic propagation.**

### New Architecture

**Ship .claude/ Directory:**
- CCS items now ship with npm/sh/ps1 packages
- Selective item-level symlinks: `~/.ccs/.claude/` → `~/.claude/`
- Auto-propagation on `npm update` - zero manual sync
- Backward compatible with existing `~/.ccs/shared/` mechanism

**Symlink Chain:**
```
~/.ccs/.claude/ (source) 
    ↓ selective symlinks
~/.claude/ (CCS items installed here)
    ↑ symlinked by
~/.ccs/shared/
    ↑ symlinked by  
profiles (work, personal, team)
```

### New Commands

**Maintenance Tools:**
- `ccs update` - Re-install CCS symlinks to ~/.claude/
- `ccs doctor` - Added Check 9: CCS symlinks health verification

**Safe Installation:**
- Automatic conflict backup before symlinking
- Idempotent operations (safe to run multiple times)
- Health monitoring and recovery

### New Components

- `bin/utils/claude-symlink-manager.js` - Manages selective symlinks
- Updated all 3 installers (npm postinstall, install.sh, install.ps1)
- Enhanced `ccs doctor` with symlink health checks

---

## 💥 Breaking Changes

**From v3.5.0 → v4.x:**

1. **Delegation commands moved**: 
   - Old: User manually created in `~/.claude/commands/`
   - New: Auto-shipped in `~/.ccs/.claude/`, symlinked to `~/.claude/commands/ccs/`

2. **Slash command format**:
   - New: `/ccs:glm`, `/ccs:kimi`, `/ccs:glm:continue`
   - Old custom commands may need migration

3. **Profile validation**:
   - Placeholders (`YOUR_API_KEY_HERE`) now detected and marked invalid
   - Must configure real API keys for delegation to work

4. **Stream output format**:
   - Headless mode (`-p`) now uses stream-JSON protocol
   - Old text output replaced with structured `{type, data}` format

scripts/postinstall.js

@@ -103,6 +103,17 @@ function createConfigFiles() {
     }
     console.log('');
 
+    // Install CCS items to ~/.claude/ (v4.1.0)
+    try {
+      const ClaudeSymlinkManager = require('../bin/utils/claude-symlink-manager');
+      const claudeSymlinkManager = new ClaudeSymlinkManager();
+      claudeSymlinkManager.install();
+    } catch (err) {
+      console.warn('[!] CCS item installation warning:', err.message);
+      console.warn('    Run "ccs update" to retry');
+    }
+    console.log('');
+
     // Create config.json if missing
     const configPath = path.join(ccsDir, 'config.json');
     if (!fs.existsSync(configPath)) {