refactor(toolchain)!: 工具链 plugindev 更名为 hmapdev，module path 改回 gitcode

- 目录 tools/plugindev → tools/hmapdev，可执行文件名/平台产物名同步
  （hmapdev_linux_amd64 等；包格式仍叫 .hmap）
- module path github.com/JianFeeeee/homeagent-sdk/tools/... → gitcode.com/...
  （与仓库实际托管一致；核心仓不依赖该 path，改动无外部影响）
- SDK 存储目录 ~/.homeagent/plugindev/sdk → ~/.homeagent/hmapdev/sdk
  新目录不存在而旧目录存在时沿用旧目录 → 已装 SDK 版本不会丢失
- 命令表/usage/--help/生成项目 README/示例 README/NSIS 安装器/
  package/build.sh/build-examples.sh 全部同步；PLUGINDEV 环境变量保留兼容
- sdk/ 目录零改动（公开接口不变）

验证：
- go build ./... ok；go test ./tools/hmapdev/ ok（含模板接线守卫 TestProcTemplate_CoversAllCoreMethods）
- bash -n package/{build,build-examples}.sh ok
- 端到端：hmapdev init demo && hmapdev build → dist/demo_bundle.hmap（linux+darwin）
- 本机安装 /usr/local/bin/hmapdev，旧名以软链保留；sdk list/current 正常

tools/hmapdev/replace.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+type GoModPatcher struct {
+	dir      string
+	replaces []string
+	backup   string
+}
+
+func NewGoModPatcher(dir string, replaces []string) *GoModPatcher {
+	return &GoModPatcher{dir: dir, replaces: replaces}
+}
+
+func (p *GoModPatcher) Apply() (func(), error) {
+	if len(p.replaces) == 0 {
+		return func() {}, nil
+	}
+
+	gomodPath := filepath.Join(p.dir, "go.mod")
+	data, err := os.ReadFile(gomodPath)
+	if err != nil {
+		return func() {}, fmt.Errorf("read go.mod: %w", err)
+	}
+	p.backup = string(data)
+
+	var sb strings.Builder
+	sb.WriteString(strings.TrimRight(string(data), "\r\n"))
+	sb.WriteString("\n")
+	for _, r := range p.replaces {
+		from, to, found := strings.Cut(r, "=")
+		if !found {
+			fmt.Printf("  warn: invalid replace %q, skipping\n", r)
+			continue
+		}
+		from = strings.TrimSpace(from)
+		to = strings.TrimSpace(to)
+		absTo, err := filepath.Abs(to)
+		if err != nil {
+			fmt.Printf("  warn: resolve path %q: %v, skipping\n", to, err)
+			continue
+		}
+		absTo = strings.ReplaceAll(absTo, "\\", "/")
+		sb.WriteString(fmt.Sprintf("replace %s => %s\n", from, absTo))
+	}
+
+	if err := os.WriteFile(gomodPath, []byte(sb.String()), 0644); err != nil {
+		return func() {}, fmt.Errorf("write go.mod: %w", err)
+	}
+
+	return p.restore, nil
+}
+
+func (p *GoModPatcher) restore() {
+	if p.backup == "" {
+		return
+	}
+	gomodPath := filepath.Join(p.dir, "go.mod")
+	os.WriteFile(gomodPath, []byte(p.backup), 0644)
+	p.backup = ""
+}
+
+func (p *GoModPatcher) ReplaceDirs() []string {
+	var dirs []string
+	for _, r := range p.replaces {
+		_, to, found := strings.Cut(r, "=")
+		if found {
+			dirs = append(dirs, strings.TrimSpace(to))
+		}
+	}
+	return dirs
+}