Recover remote history metadata payloads

Author: SqlRush

docs/cc-100-roadmap.md

@@ -558,7 +558,7 @@ M7 补充：prompt history `LogEntry` 读取现在接受 `sessionID`/`session`/`
 
 本轮补充：contract image source 解码现在接受 `mediaType`/`mimeType`/`contentType`、`base64`/`payload` 等 source 字段别名，并支持顶层 image block 直接携带媒体类型和 base64 数据，transcript resume 会保留为规范 `ImageSource`。
 
-本轮补充：remote history `SDKEvent` payload materialization 现在会递归解包 `payload`/`data`/`body` 内的 `record`/`entry`/`item`/`event`/`result`/`response`/`output` wrapper，减少远端事件多层包装导致的消息丢失。
+本轮补充：remote history `SDKEvent` payload materialization 现在会递归解包 `payload`/`data`/`body`/`metadata`/`meta`/`attributes`/`properties` 内的 `record`/`entry`/`item`/`event`/`result`/`response`/`output` wrapper，减少远端事件多层包装导致的消息丢失。
 
 本轮补充：remote history 普通事件数组现在也会解包元素级 `event`/`record`/`entry`/`item`/`resource`/`value` 以及无事件本体字段时的 `data`/`payload`/`body` wrapper，并用元素 `cursor` 作为事件 ID fallback，覆盖非 GraphQL edges 的 wrapper item 响应。
 

docs/claude-code-go-rewrite-plan.md

@@ -215,7 +215,7 @@ test/parity/                 # golden tests against TS/official behavior
 - 本轮补充：remote history response parser 现在也接受 JSON:API `included` collection，会过滤非事件资源，并递归解包 `resource`/`attributes`/`properties` 后保留外层 resource id 作为事件 ID fallback。
 - 本轮补充：remote history response parser 会解包 `payload`/`response`/`result`/`body` 等通用响应外壳，外壳内的 event list、pagination、links 会继续递归解析。
 - 本轮补充：remote history response parser 现在也接受 provider-style `choices`/`outputs`/`candidates`/`generations` wrapper，可从 `message.content`、content-block array 和 `content.parts[].text` 中恢复 event page JSON（包括 fenced `json` code block），并保留 pagination 继续驱动 `before_id` 续抓。
-- 本轮补充：remote history `SDKEvent` 本体接受 `eventType`/`event_type`/`role` 类型别名、`createdAt`/`created_at` 时间戳别名，以及 `payload`/`data`/`body`/`serializedMessage` message payload 别名；payload 只有 `role`/`content` 时也能 materialize 成 transcript message。
+- 本轮补充：remote history `SDKEvent` 本体接受 `eventType`/`event_type`/`role` 类型别名、`createdAt`/`created_at` 时间戳别名，以及 `payload`/`data`/`body`/`metadata`/`meta`/`attributes`/`properties`/`serializedMessage` message payload 别名；payload 只有 `role`/`content` 时也能 materialize 成 transcript message。
 - 本轮补充：transcript resume 的嵌套 content block 接受 `toolUseId`/`toolUseID`、`isError`、`cacheControl`、`cacheReference` 字段别名，并保留 cache edit 的 `cacheReference`。
 - 本轮补充：transcript resume 的 nested content block `id`/`tool_use_id`/`toolUseId` 现在接受 JSON number，并保留为字符串 tool-use ID。
 - 本轮补充：嵌套 contract message 的 `content` 接受字符串、单个 content-block 对象，以及混合字符串/content-block 数组；字符串会归一为 text block，并接受 `text`/`body`/`message`/`value`/`output` 正文字段和 `role`/`messageType` 类型别名，提升 transcript/remote history payload 恢复率。

docs/first-second-parity-audit.md

@@ -169,7 +169,7 @@ M6 progress now includes:
 - `internal/session`: remote-history parsing now also accepts `value`, `values`, `resources`, and `collection` event-list aliases, plus `edges[].resource`/`edges[].value` node payload aliases.
 - `internal/session`: remote-history parsing now unwraps generic response envelopes such as `payload`, `response`, `result`, and `body` when they contain event lists and pagination fields.
 - `internal/session`: remote-history event-list fields such as `data` and `result` now accept a single SDK event object directly, preserving non-array single-event pages instead of treating them only as wrappers.
-- `internal/contracts`/`internal/session`: remote-history event materialization now accepts `eventType`/`event_type`/`role` type aliases, `createdAt`/`created_at` timestamp aliases, and message payload aliases such as `payload`, `data`, `body`, and `serializedMessage`, including role/content-only payloads.
+- `internal/contracts`/`internal/session`: remote-history event materialization now accepts `eventType`/`event_type`/`role` type aliases, `createdAt`/`created_at` timestamp aliases, and message payload aliases such as `payload`, `data`, `body`, `metadata`, `meta`, `attributes`, `properties`, and `serializedMessage`, including role/content-only payloads.
 - `internal/session`: remote-history pageInfo parsing now accepts previous/older pagination signals such as `hasPrevious`/`hasPreviousPage`, `hasOlder`/`more`, and before-id cursors such as `previousCursor`/`prevCursor`/`beforeCursor`/`olderCursor`.
 - `internal/session`: remote-history pagination bool parsing now accepts numeric and yes/no-style bool values in addition to JSON bools and true/false strings.
 - `internal/session`: remote-history pagination cursor/id parsing now accepts JSON numbers and preserves them as string cursors for page fields and `edges[].cursor`.

internal/contracts/session.go

@@ -235,6 +235,18 @@ func (e *SDKEvent) UnmarshalJSON(data []byte) error {
 			aux.Item,
 		)
 	}
+	if e.Message == nil {
+		fields := map[string]json.RawMessage{}
+		if err := json.Unmarshal(data, &fields); err == nil {
+			e.Message = firstSDKEventSidecarMessage(e.Type,
+				fields["metadata"],
+				fields["meta"],
+				fields["attributes"],
+				fields["properties"],
+				fields["attrs"],
+			)
+		}
+	}
 	if e.Message == nil {
 		e.Message = sdkEventTopLevelMessage(data, e.Type)
 	}
@@ -326,6 +338,26 @@ func sdkEventMessageFromRaw(raw json.RawMessage, eventType SDKEventType) *Messag
 			return nested
 		}
 	}
+	for _, name := range []string{
+		"metadata",
+		"meta",
+		"attributes",
+		"properties",
+		"attrs",
+	} {
+		if nested := sdkEventMessageFromRaw(fields[name], eventType); nested != nil && sdkEventTopLevelMessageHasData(*nested) {
+			return nested
+		}
+	}
+	return nil
+}
+
+func firstSDKEventSidecarMessage(eventType SDKEventType, values ...json.RawMessage) *Message {
+	for _, value := range values {
+		if message := sdkEventMessageFromRaw(value, eventType); message != nil && sdkEventTopLevelMessageHasData(*message) {
+			return message
+		}
+	}
 	return nil
 }
 

internal/session/remote_history_test.go

@@ -1749,6 +1749,29 @@ func TestRemoteHistoryTranscriptMessagesAcceptsNestedEventPayloadWrappers(t *tes
 	}
 }
 
+func TestRemoteHistoryTranscriptMessagesAcceptsMetadataPayloadWrappers(t *testing.T) {
+	var response sessionEventsResponse
+	if err := json.Unmarshal([]byte(`{"events":[
+		{"eventType":"user","eventId":"evt_u_meta","sessionID":"s_meta","createdAt":"2026-01-01T00:00:01Z","metadata":{"role":"user","text":"metadata hi"}},
+		{"eventType":"assistant","eventId":"evt_a_props","sessionID":"s_meta","parentMessageID":"evt_u_meta","createdAt":"2026-01-01T00:00:02Z","properties":{"message":{"role":"assistant","message":"properties hello"}}}
+	]}`), &response); err != nil {
+		t.Fatal(err)
+	}
+	messages := RemoteHistoryTranscriptMessages(response.Events)
+	if len(messages) != 2 || messages[0].UUID != "evt_u_meta" || messages[1].UUID != "evt_a_props" {
+		t.Fatalf("messages = %#v", messages)
+	}
+	if messages[0].Message == nil || len(messages[0].Message.Content) != 1 || messages[0].Message.Content[0].Text != "metadata hi" {
+		t.Fatalf("metadata payload = %#v", messages[0].Message)
+	}
+	if messages[1].Message == nil || len(messages[1].Message.Content) != 1 || messages[1].Message.Content[0].Text != "properties hello" {
+		t.Fatalf("properties payload = %#v", messages[1].Message)
+	}
+	if messages[1].ParentUUID == nil || *messages[1].ParentUUID != "evt_u_meta" || messages[1].Message.ParentUUID == nil || *messages[1].Message.ParentUUID != "evt_u_meta" {
+		t.Fatalf("parent linkage = %#v message=%#v", messages[1].ParentUUID, messages[1].Message)
+	}
+}
+
 func TestRemoteHistoryTranscriptMessagesAcceptsNumericIDAliases(t *testing.T) {
 	var response sessionEventsResponse
 	if err := json.Unmarshal([]byte(`{"events":[{"type":"user","id":101,"sessionId":7,"timestamp":"2026-01-01T00:00:01Z","message":{"type":"user","content":[{"type":"text","text":"hi"}]}},{"type":"assistant","eventId":102,"sessionId":7,"parentMessageID":101,"timestamp":"2026-01-01T00:00:02Z","message":{"type":"assistant","content":[{"type":"text","text":"hello"}]}}]}`), &response); err != nil {