Revisions updated by `dart tools/rev_sdk_deps.dart`.

ai (https://github.com/dart-lang/ai/compare/bc90433..078abd2):
  078abd2  2025-09-16  Greg Spencer  Remove a reference to screenshots for generic error (dart-lang/ai#280)

dartdoc (https://github.com/dart-lang/dartdoc/compare/49fc272..4df6dbe):
  4df6dbe5  2025-09-18  Sarah Zakarias  Undo deprecation of api exports (dart-lang/dartdoc#4105)

http (https://github.com/dart-lang/http/compare/ef05b37..d8e6929):
  d8e6929  2025-09-18  Brian Quinlan  Only set the charset when the body is set for certain mime types (dart-lang/http#1798)

protobuf (https://github.com/dart-lang/protobuf/compare/971bcae..456e2ee):
  456e2ee  2025-09-16  Ömer Sinan Ağacan  Generate unittest_features proto (google/protobuf.dart#1051)
  c215029  2025-09-16  Ömer Sinan Ağacan  Update pre-generated protos (google/protobuf.dart#1050)

tools (https://github.com/dart-lang/tools/compare/4254267..042b03e):
  042b03e8  2025-09-17  Devon Carew  rev package:pool in prep for publishing (dart-lang/tools#2166)

Change-Id: I14a1b43be92702489925dd7968853ef043d42bfa
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/450363
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Devon Carew <devoncarew@google.com>