feat: L0b bootstrap scripts + L1 Go CLI structure

L0b (factory bootstrap):
- bootstrap.ps1 (Windows): pre-checks, interactive config, clone .factory, home.toml
- bootstrap.sh (Linux/Mac): same functionality for bash
- Idempotent re-run with home.toml verification

L1 (Go CLI):
- factory.yaml: manifest schema with components, deps, health-checks
- cmd/factory: Cobra CLI (install/update/status/diagnose)
- pkg/config: home.toml reader
- pkg/manifest: factory.yaml parser + topological sort
- pkg/health: health-check logic (file/dir/mcp_tool/command)

Scripts:
- build.sh: cross-compile for linux/win/darwin × amd64/arm64
- build.ps1: PowerShell cross-compile

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

pkg/config/home.go

@@ -0,0 +1,57 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/BurntSushi/toml"
+)
+
+type HomeConfig struct {
+	ProjectsDir string    `toml:"projects_dir"`
+	Client      string    `toml:"client"`
+	InstalledAt time.Time `toml:"installed_at"`
+}
+
+func GetHomePath() string {
+	homeDir, _ := os.UserHomeDir()
+	return filepath.Join(homeDir, ".config", "factory", "home.toml")
+}
+
+func LoadHome() (*HomeConfig, error) {
+	path := GetHomePath()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("home.toml not found at %s (run L0b bootstrap first)", path)
+	}
+
+	var cfg HomeConfig
+	if err := toml.Unmarshal(data, &cfg); err != nil {
+		return nil, fmt.Errorf("failed to parse home.toml: %w", err)
+	}
+
+	// Validate
+	if cfg.ProjectsDir == "" {
+		return nil, fmt.Errorf("projects_dir is required in home.toml")
+	}
+	if cfg.Client == "" {
+		cfg.Client = "claude-code"
+	}
+
+	return &cfg, nil
+}
+
+func (h *HomeConfig) GetFactoryDir() string {
+	return filepath.Join(h.ProjectsDir, ".factory")
+}
+
+func (h *HomeConfig) GetManifestPath() string {
+	return filepath.Join(h.GetFactoryDir(), "factory.yaml")
+}
+
+func (h *HomeConfig) GetCommonDir() string {
+	return filepath.Join(h.ProjectsDir, ".common")
+}