Optimize the S3 GET path for chunked/multipart objects and reduce Telegram
API round-trips:
- object-stream: fetch object parts concurrently (bounded, in-order fan-in)
instead of serializing N sequential Telegram CDN fetches. Response latency
is now ~the slowest part fetch, not the sum of all part fetches.
- bot-pool.getFileInfo: cache file_id -> file_path in the existing in-memory
cache so repeated S3 GET/HEAD of the same object skip the Telegram API call
(file-controller had its own cache wrapper; the S3 path did not).
- chunked-storage + s3-controller: resolve multipart/chunked part CDN URLs
concurrently via Promise.all instead of sequentially.
- s3-controller multipart: await writer.end() before re-reading the temp part
file to avoid a flush race.
Adds object-stream-parallel.test.ts covering in-order fan-in, byte ranges,
and single-part responses even when the slowest part resolves out of order.
asepharyana
43e36b7629