Sibling sweep from the #58902 raft review found aiohttp servers still
running on the implicit 1 MiB default with no explicit body cap:
- bluebubbles webhook (127.0.0.1): 1 MiB explicit cap — events are small
JSON/form payloads; attachments arrive via the REST API
- teams Bot Framework listener (0.0.0.0 bind — most exposed): 1 MiB cap;
activities are JSON well under that
- hermes proxy server: 10 MB cap mirroring api_server's MAX_REQUEST_BYTES
(chat-completion payloads can be large, but must stay bounded)
client_max_size bounds every read path including chunked transfer-encoding
requests that carry no Content-Length (#58536/#58902 pattern).
Deliberately excluded: feishu, whatsapp_cloud, sms, line, wecom, msgraph —
open contributor PRs (#54938, #54944, #54620, #54931, #54934, #25296)
already cover those; reviewing them separately preserves their credit.
3 regression tests pin the wiring.
