feat: complete HomeAgent architecture v2

- IO abstraction layer with OutputChannel routing and capability validation
- Three-layer memory (Context-Document-Graph) with TF-IDF relevance pruning
- OneBot V11 QQ protocol plugin with Reverse WebSocket client
- Plugin system with hot-reload (SKILL.md + native factories)
- Knowledge system with TF-IDF vector indexing
- Personality system (personal.md)
- Text memory (JSONL with rotation)
- Change tracker (overlayfs) with rollback
- Lua adapter VM
- Design document (DESIGN.md)

Module: gitcode.com/JianFeeeee/HomeAgent

internal/agent/personal.go

@@ -0,0 +1,41 @@
+package agent
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+type Personality struct {
+	Content string
+	Path    string
+}
+
+func LoadPersonality(path string) (*Personality, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return &Personality{}, nil
+		}
+		return nil, fmt.Errorf("read personal.md: %w", err)
+	}
+	return &Personality{
+		Content: string(data),
+		Path:    path,
+	}, nil
+}
+
+func SavePersonality(path, content string) error {
+	dir := filepath.Dir(path)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("create personality dir: %w", err)
+	}
+	return os.WriteFile(path, []byte(content), 0644)
+}
+
+func (p *Personality) InjectPrompt() string {
+	if p.Content == "" {
+		return ""
+	}
+	return fmt.Sprintf("【人格设定】\n%s\n", p.Content)
+}