feat(llm): send DeepSeek user identity header

docs/subsystems/llm-streaming.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write docs/subsystems/llm-streaming.md
-llm-streaming.md: bd2c9b856d34e625b023a20c8be331eb7ea89880
-llm-streaming.zh.md: 34420669ca8cbdf9d9a0d8b38e67bc196c290cc8
+llm-streaming.md: 41ae943b1945209bc7996379dc326434b5803d17
+llm-streaming.zh.md: b67cdfd4eb5a3c1320e7afe333d4d06516295f7d

docs/subsystems/llm-streaming.md

@@ -484,8 +484,8 @@ interface GenerateOptions {
   stop?: string[]
   signal?: AbortSignal
   /**
-   * Session identity stamped by the loop for listener routing. Adapters ignore
-   * it; replay uses it to keep concurrent parent and child cursors independent.
+   * Session identity stamped by the loop for request routing. Replay uses it
+   * to separate cursors; adapters may map it to model-hidden transport metadata.
    */
   sessionId?: Branded<'SessionId'>
   /**

docs/subsystems/llm-streaming.zh.md

@@ -492,8 +492,8 @@ interface GenerateOptions {
   stop?: string[]
   signal?: AbortSignal
   /**
-   * Session identity stamped by the loop for listener routing. Adapters ignore
-   * it; replay uses it to keep concurrent parent and child cursors independent.
+   * Session identity stamped by the loop for request routing. Replay uses it
+   * to separate cursors; adapters may map it to model-hidden transport metadata.
    */
   sessionId?: Branded<'SessionId'>
   /**