fix(todo-continuation): send runtime agent display name

[Gujiassh]

Summary

• ensure todo-continuation-enforcer prefers the runtime display name when only a config key is available so injected agent names match what the server advertises
• derive the runtime display name via the shared agent display-name helpers when resolveRegisteredAgentName cannot find a prettier alias
• add a regression test covering the fallback path

Testing

• bun test src/hooks/todo-continuation-enforcer/continuation-injection.test.ts

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Summary by cubic

Send the runtime agent display name during todo continuation injection so the injected agent matches the server-advertised name. Falls back from config key to the runtime display name when no registered alias is found.

• Bug Fixes
  • Prefer runtime display name via getAgentRuntimeName when resolveRegisteredAgentName can’t find an alias; keep alias when it differs from input.
  • Added a regression test covering the fallback path in continuation-injection.test.ts.

^{Written for commit 326e49f. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

_{Auto-approved: Fixes agent name mismatch by preferring runtime display names to align with server expectations. Includes regression tests and the logic correctly handles fallback cases.}