[RaphaelFakhri]

Summary

Fixes #1243.

RoomConfiguration and RoomAgentDispatch read only snake_case keys such as agent_name, empty_timeout and max_participants. That matches the token endpoint request format, but LiveKit tokens write the roomConfig claim as protobuf JSON with camelCase keys (agentName, emptyTimeout, maxParticipants). The Go (protojson.Marshal in livekit/protocol auth/grants.go), Python (MessageToDict) and Node server SDKs all produce camelCase keys. As a result, TokenSourceResponse.jwtPayload?.roomConfiguration returned null for every field except name, metadata and the agents list, and each agent had a null agentName.

This change:

• Makes RoomConfiguration.fromJson and RoomAgentDispatch.fromJson fall back to the camelCase key when the snake_case key is absent, the same way TokenSourceResponse.fromJson already accepts both forms.
• Leaves toJson unchanged, so token endpoint requests still use snake_case keys.

Test plan

• test/token/token_source_test.dart: the new parses room configuration from the camelCase keys of the roomConfig claim test builds a token with the keys that LiveKit tokens use and checks every field.
• Before the change the test fails with Expected: <300>, Actual: <null> on config.emptyTimeout. After the change it passes.
• The existing snake_case test still passes.
• flutter test, flutter analyze, dart format --set-exit-if-changed and import_sorter pass.
• Added a .changes entry.

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.