* fix(gateway): increase WebSocket max payload to 5 MB for image uploads
The 512 KB limit was too small for base64-encoded images — a 400 KB
image becomes ~532 KB after encoding, exceeding the limit and closing
the connection with code 1006.
Bump MAX_PAYLOAD_BYTES to 5 MB and MAX_BUFFERED_BYTES to 8 MB to
support standard image uploads via webchat.
Closes#14400
* fix: align gateway WS limits with 5MB image uploads (#14486) (thanks @0xRaini)
* docs: fix changelog conflict for #14486
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Co-authored-by: 0xRaini <0xRaini@users.noreply.github.com>
Co-authored-by: Peter Steinberger <steipete@gmail.com>
