fix(ai): memoized PI_REQ_DEBUG response-log close to avoid truncated body on cancel

packages/ai/CHANGELOG.md

@@ -27,6 +27,7 @@
 - Fixed the HTTP 400 raw-request dumper (`appendRawHttpRequestDumpFor400`) littering the real `~/.omp/logs/http-400-requests` directory during tests. Provider suites exercise the 400 error path with mocked `fetch` responses, which the dumper could not distinguish from genuine failures; it now skips persistence under the Bun test runner (`isBunTestRuntime()`).
 - Fixed Anthropic Opus requests unnecessarily forcing `tool_choice.disable_parallel_tool_use`, allowing Claude Opus to use the provider's default parallel tool-calling behavior again.
 - Fixed parallel `function_call` items losing arguments against llama.cpp's OpenAI Responses endpoint (`/v1/responses`), where every call but the last finalized with `{}` and the agent rejected them with `path: Invalid input: expected string, received undefined`. llama.cpp's `to_json_oaicompat_resp` emits `output_item.added` with only `item.call_id` (no `item.id`, no `output_index`) while the matching `function_call_arguments.delta` carries `item_id: "fc_<call_id>"`. `processResponsesStream` now registers function-call and custom-tool-call items under `item.call_id` as a secondary lookup key (alongside `item.id`/`output_index`) so identifier-deviant hosts route deltas and done events to the right block. ([#2015](https://github.com/can1357/oh-my-pi/issues/2015))
+- Fixed `PI_REQ_DEBUG` response recording truncating the captured body when a streamed response was cancelled mid-flight. The response tee in `wrapResponse` could call `FileRequestDebugResponseLog.close()` from both the `cancel` callback and the resumed `pull` (which observes `done` once the source reader is cancelled); the second caller saw the handle already nulled and returned before the first caller's pending write flushed, so the `.res.log` lost the already-buffered chunk. `close()` now memoizes its flush-and-close promise so every caller awaits the same completion.
 
 ## [15.10.0] - 2026-06-06
 

packages/ai/src/utils/request-debug.ts

@@ -170,6 +170,7 @@ class FileRequestDebugSession implements RequestDebugSession {
 class FileRequestDebugResponseLog implements RequestDebugResponseLog {
 	#handle: fs.FileHandle | undefined;
 	#pending: Promise<void> = Promise.resolve();
+	#closed: Promise<void> | undefined;
 
 	constructor(handle: fs.FileHandle) {
 		this.#handle = handle;
@@ -184,15 +185,19 @@ class FileRequestDebugResponseLog implements RequestDebugResponseLog {
 		});
 	}
 
-	async close(): Promise<void> {
+	close(): Promise<void> {
+		if (this.#closed) return this.#closed;
 		const handle = this.#handle;
-		if (!handle) return;
+		if (!handle) return Promise.resolve();
 		this.#handle = undefined;
-		try {
-			await this.#pending;
-		} finally {
-			await handle.close();
-		}
+		this.#closed = (async () => {
+			try {
+				await this.#pending;
+			} finally {
+				await handle.close();
+			}
+		})();
+		return this.#closed;
 	}
 }