Remove client-side auto-review from app

[OpenCodeEngineer]

Remove all remaining client-side auto-review code from the app package. This includes deleting the session auto-review module/tests, removing session follow-up wiring, removing the app setting and UI toggle, and cleaning up related i18n strings. Verify with cd packages/app && bun typecheck and cd packages/opencode && bun typecheck.

[OpenCodeEngineer]

Status update: implemented the app-side auto-review removal and verified local typechecks pass in packages/app and packages/opencode. Reviewing the resulting diff now before final handoff.

[OpenCodeEngineer]

Final status: app-side client auto-review removal is complete. Deleted the session auto-review module and tests, removed the session wiring/state, removed the settings toggle and related i18n strings, and confirmed there are no remaining app-side auto-review references with a repo search. Local verification passed with cd packages/app && bun typecheck and cd packages/opencode && bun typecheck. No commit or PR created.

[dzianisv]

Duplicate of #204.