✨ feat(spx): issue marker 支持第三种类型 prototype

- --type 三选一 spec|plan|prototype，marker 行写 <!-- spx:prototype=路径 -->，
  与 spec/plan 共用同一套增量更新逻辑；类型→state 字段的映射收成一张表
- 同步写 state JSON 的 prototypeFile（pattern 要求 dir/.../x.json）
- 顺手补上 b62e58d 漏掉的 prototypeSessionId / prototypeProfilePath：
  schema 与 knownStateFields 都没有它们，带原型会话的工单一 merge
  就会被 additionalProperties 拒掉

Claude-Session: https://claude.ai/code/session_01Kgmb1LvrPmFX3NoUDB4zZC

vscode/cli/cmd/spx/main.go

@@ -111,6 +111,20 @@ func buildRootCmd() *cobra.Command {
 	return root
 }
 
+// markerTypeToStateField maps a `spx issue marker --type` value to the state
+// JSON field it mirrors. All three types share one incremental-update path;
+// this table is the single source of truth — adding a type only touches it
+// (plus markerTypesHint below, which is what the user sees).
+var markerTypeToStateField = map[string]string{
+	"spec":      "specFile",
+	"plan":      "planFile",
+	"prototype": "prototypeFile",
+}
+
+// markerTypesHint is the human-readable enumeration used in help text and the
+// "bad --type" error, kept next to the table so the two can't drift.
+const markerTypesHint = "spec、plan 或 prototype"
+
 func buildIssueCmd() *cobra.Command {
 	issue := &cobra.Command{
 		Use:   "issue",
@@ -215,17 +229,17 @@ func buildIssueCmd() *cobra.Command {
 
 	markerCmd := &cobra.Command{
 		Use:   "marker",
-		Short: "增量更新现有工单的 spec/plan marker，并同步合并 specFile/planFile 进 state JSON",
+		Short: "增量更新现有工单的 spec/plan/prototype marker，并同步合并 specFile/planFile/prototypeFile 进 state JSON",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			if imIssue <= 0 {
 				return fmt.Errorf("--issue 必须是正整数")
 			}
-			if imType != "spec" && imType != "plan" {
-				return fmt.Errorf("--type 必须是 spec 或 plan，得到 %q", imType)
+			fieldName, ok := markerTypeToStateField[imType]
+			if !ok {
+				return fmt.Errorf("--type 必须是 %s，得到 %q", markerTypesHint, imType)
 			}
 			// Fail fast on a bad path before we touch the network — the
-			// schema's specFile/planFile pattern doubles as input check.
-			fieldName := map[string]string{"spec": "specFile", "plan": "planFile"}[imType]
+			// schema's pattern for this field doubles as input check.
 			patch := map[string]any{fieldName: imValue}
 			if err := state.ValidateValue(patch); err != nil {
 				return err
@@ -263,8 +277,8 @@ func buildIssueCmd() *cobra.Command {
 		},
 	}
 	markerCmd.Flags().IntVar(&imIssue, "issue", 0, "工单编号（必填）")
-	markerCmd.Flags().StringVar(&imType, "type", "", "marker 类型：spec 或 plan（必填）")
-	markerCmd.Flags().StringVar(&imValue, "value", "", "marker 值（路径，必填，同步写入 state JSON 的 specFile/planFile）")
+	markerCmd.Flags().StringVar(&imType, "type", "", "marker 类型："+markerTypesHint+"（必填）")
+	markerCmd.Flags().StringVar(&imValue, "value", "", "marker 值（路径，必填，同步写入 state JSON 的 specFile/planFile/prototypeFile）")
 	_ = markerCmd.MarkFlagRequired("issue")
 	_ = markerCmd.MarkFlagRequired("type")
 	_ = markerCmd.MarkFlagRequired("value")
@@ -394,11 +408,14 @@ var knownStateFields = map[string]struct{}{
 	"implementSessionId":    {},
 	"reviewSessionId":       {},
 	"testSessionId":         {},
+	"prototypeSessionId":    {},
 	"profilePath":           {},
 	"brainstormProfilePath": {},
 	"testProfilePath":       {},
+	"prototypeProfilePath":  {},
 	"specFile":              {},
 	"planFile":              {},
+	"prototypeFile":         {},
 	"prDiffFile":            {},
 	"pr":                    {},
 	"prMerged":              {},

vscode/cli/internal/marker/marker_test.go

@@ -29,16 +29,38 @@ func TestUpsertMarkerReplacesWhenPresent(t *testing.T) {
 }
 
 func TestUpsertMarkerLeavesOtherTypesAlone(t *testing.T) {
-	body := "<!-- spx:plan=p.md -->\n<!-- spx:spec=old.md -->"
+	body := "<!-- spx:plan=p.md -->\n<!-- spx:prototype=docs/prototype/x/figma-plugin/manifest.json -->\n<!-- spx:spec=old.md -->"
 	got := UpsertMarker(body, "spec", "new.md")
 	if !strings.Contains(got, "<!-- spx:plan=p.md -->") {
 		t.Fatalf("plan marker should be preserved: %q", got)
 	}
+	if !strings.Contains(got, "<!-- spx:prototype=docs/prototype/x/figma-plugin/manifest.json -->") {
+		t.Fatalf("prototype marker should be preserved: %q", got)
+	}
 	if !strings.Contains(got, "<!-- spx:spec=new.md -->") {
 		t.Fatalf("spec marker should be updated: %q", got)
 	}
 }
 
+func TestUpsertMarkerPrototypeAppendsWhenAbsent(t *testing.T) {
+	got := UpsertMarker("hello body", "prototype", "docs/prototype/login/figma-plugin/manifest.json")
+	want := "hello body\n<!-- spx:prototype=docs/prototype/login/figma-plugin/manifest.json -->"
+	if got != want {
+		t.Fatalf("got %q want %q", got, want)
+	}
+}
+
+func TestUpsertMarkerPrototypeReplacesWhenPresent(t *testing.T) {
+	body := "intro\n<!-- spx:prototype=old/manifest.json -->\nmore"
+	got := UpsertMarker(body, "prototype", "new/manifest.json")
+	if strings.Contains(got, "old/manifest.json") {
+		t.Fatalf("old value should be gone: %q", got)
+	}
+	if !strings.Contains(got, "<!-- spx:prototype=new/manifest.json -->") {
+		t.Fatalf("new marker missing: %q", got)
+	}
+}
+
 func TestUpsertMarkerEmptyBody(t *testing.T) {
 	got := UpsertMarker("", "plan", "p.md")
 	want := "<!-- spx:plan=p.md -->"

vscode/cli/internal/state/schema.json

@@ -31,6 +31,11 @@
       "description": "测试阶段的 Claude Code session id；PR 合并后手动启动的测试会话，用于 resume。",
       "minLength": 1
     },
+    "prototypeSessionId": {
+      "type": "string",
+      "description": "原型阶段的 Claude Code session id；画 Figma 原型的会话，用于 resume。",
+      "minLength": 1
+    },
     "profilePath": {
       "type": "string",
       "description": "创建工单时使用的 Claude settings 配置文件绝对路径，resume 时作为 --settings 传入。",
@@ -46,6 +51,11 @@
       "description": "测试会话使用的 Claude settings 配置文件绝对路径；与实施 profilePath 独立，空则用默认。",
       "minLength": 1
     },
+    "prototypeProfilePath": {
+      "type": "string",
+      "description": "原型会话使用的 Claude settings 配置文件绝对路径；与实施 profilePath 独立，空则用默认。",
+      "minLength": 1
+    },
     "specFile": {
       "type": "string",
       "description": "本工单的 spec 文档路径，相对 workspace，必须形如 `dir/.../name.md`。",
@@ -58,6 +68,12 @@
       "minLength": 1,
       "pattern": "^[^\\s]+/[^\\s]+\\.md$"
     },
+    "prototypeFile": {
+      "type": "string",
+      "description": "本工单的 Figma 原型插件 manifest.json 路径，仓库相对或绝对，必须形如 `dir/.../manifest.json`。",
+      "minLength": 1,
+      "pattern": "^[^\\s]+/[^\\s]+\\.json$"
+    },
     "prDiffFile": {
       "type": "string",
       "description": "本工单的 PR 变更摘要文件路径，相对 workspace，必须位于 docs/pr-diff/ 下。",

vscode/cli/internal/state/schema_test.go

@@ -71,11 +71,14 @@ func TestValidateAcceptsFullState(t *testing.T) {
         "implementSessionId":"impl-1",
         "reviewSessionId":"rev-1",
         "testSessionId":"test-1",
+        "prototypeSessionId":"proto-1",
         "profilePath":"/home/x/.claude/settings.json",
         "brainstormProfilePath":"/home/x/.claude/profiles/brainstorm.json",
         "testProfilePath":"/home/x/.claude/profiles/test.json",
+        "prototypeProfilePath":"/home/x/.claude/profiles/prototype.json",
         "specFile":"docs/superpowers/specs/foo.md",
         "planFile":"docs/superpowers/plans/foo.md",
+        "prototypeFile":"docs/prototype/login/figma-plugin/manifest.json",
         "prDiffFile":"docs/pr-diff/pr-42-issue-7.md",
         "pr":"42",
         "prMerged":true,
@@ -91,6 +94,13 @@ func TestValidateAcceptsFullState(t *testing.T) {
 	}
 }
 
+func TestValidateRejectsBadPrototypeFile(t *testing.T) {
+	err := Validate([]byte(`{"prototypeFile":"docs/prototype/login/figma-plugin/manifest.md"}`))
+	if err == nil {
+		t.Fatal("非 .json 路径应当被 prototypeFile pattern 拒绝")
+	}
+}
+
 func TestValidateAcceptsBrainstormProfilePathOnly(t *testing.T) {
 	if err := Validate([]byte(`{"brainstormProfilePath":"/home/x/.claude/profiles/brainstorm.json"}`)); err != nil {
 		t.Fatalf("仅含 brainstormProfilePath 应当通过校验，得到: %v", err)