Add Opencode GO Session Id

[TheGreatAxios]

Summary

• Forward the active Corbits session through OpenCode Go Chat, Responses, and Messages transports
• Rebuild source options after /clear and /new session rotation without changing request bodies

Verification

• Focused adapter and source propagation tests pass
• bun run test passes
• bun run typecheck and bun run build pass
• bun run check reaches lint but fails on the repository's pre-existing lint warnings

Fixes CL-7504

[linear-code]

CL-7504

[TheGreatAxios]

Critic · Comment

OpenCode Go sources carry x-opencode-session through chat, responses, and messages adapters, and the source is rebuilt on TUI session rotation.

Findings

• src/tui/runner.ts:1231-1258,1443-1450 — /clear or /new rebuilds liveSource with the new session, but activeCodexSource/activeXaiSource retain the pre-rotation source. The next send on a Codex or xAI profile runs the refresh path and assigns that old source back to liveSource, so its session marker regresses to the old session.
• src/provider/openai-responses-adapter.ts:209-218 and src/config.test.ts:1257-1266 — the Responses adapter reads openaiSessionId, while the new canonical OpenCode marker is opencodeSessionId; the test checks only source defaults, not the built Responses request. A request using only opencodeSessionId therefore omits the header, and a future source change could pass the test while breaking the Responses wire path.

Notes

• No test covers the actual TUI rotation-to-next-request marker, or registry resolution plus wire headers for all three protocols.
• Focused tests pass; the full suite had an unrelated reactor-empty-turn timeout in this run.