fix(server): preserve reasoning effort after restart

[IgniparousTempest]

Restart reconciliation resumed provider turns without the thread model selection. Codex therefore rebuilt collaboration settings with its medium-effort fallback, even when the interrupted turn used high or xhigh reasoning.

Forward the persisted thread model selection on automatic continuation. Extend the reconciliation and SQLite-backed startup tests to prove a high-effort selection survives restart, and cover the resulting Codex turn parameters and developer instructions.

Closes #10928.

Verification:

• vp test run apps/server/src/serverRuntimeStartup.reconcile.test.ts apps/server/src/provider/Layers/CodexSessionRuntime.test.ts
• vp test run apps/server/integration/orphanedProviderSessionStartup.integration.test.ts
• vp test run apps/server/src/provider/Layers/CodexAdapter.test.ts
• vp run --filter t3 typecheck
• targeted lint and formatting checks

Model: GPT-5.6 via Codex.

Summary by CodeRabbit

• Bug Fixes

  • Preserved model selection details, including reasoning effort, when continuing sessions after a server restart.
  • Ensured recovered and promptless continuations use the configured provider, model, and reasoning settings.

• Tests

  • Added coverage confirming reasoning effort is retained in collaboration settings and provider instructions.

[macroscopeapp]

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — The PR is a focused restart-recovery fix, but it changes an existing automatic continuation path by applying persisted model and reasoning settings that were previously omitted. Because those settings alter downstream model processing behavior, human review is warranted despite the small, well-tested diff.

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[coderabbitai]

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ℹ️ Recent review info

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Plan: Advanced

Run ID: f6b183cc-9dcc-4ea4-93c3-d49a22e0b2ad

📥 Commits

Reviewing files that changed from the base of the PR and between 6c58362 and 20967e2.

📒 Files selected for processing (4)

• apps/server/integration/orphanedProviderSessionStartup.integration.test.ts
• apps/server/src/provider/Layers/CodexSessionRuntime.test.ts
• apps/server/src/serverRuntimeStartup.reconcile.test.ts
• apps/server/src/serverRuntimeStartup.ts

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📝 Walkthrough

Walkthrough

The restart continuation path now passes the recovered thread’s modelSelection to the provider. Tests verify preservation of Codex reasoning effort through reconciliation, orphaned-session startup, and Codex parameter construction.

Changes

Restart continuation model selection

Layer / File(s)	Summary
Propagate selection through restart reconciliation apps/server/src/serverRuntimeStartup.ts, apps/server/src/serverRuntimeStartup.reconcile.test.ts	Restart continuations now send each recovered thread’s modelSelection. Reconciliation fixtures and expectations cover normal and recovered continuation paths.
Validate Codex reasoning effort preservation apps/server/src/provider/Layers/CodexSessionRuntime.test.ts, apps/server/integration/orphanedProviderSessionStartup.integration.test.ts	Tests verify that "high" reasoning effort reaches Codex collaboration settings, developer instructions, and orphaned-session continuation input.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Severity of issue fixed: Low

Merge Risk: ⚪ Minimal · up to 20967

Interrupted Codex turns resumed after restart retain their saved model and reasoning-effort settings, preventing fallback to medium effort. The change is covered across reconciliation and startup continuation paths and is ready to merge.

Suggested reviewers: maria-rcks, t3dotgg, juliusmarminge

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: preserving reasoning effort after a server restart.
Description check	✅ Passed	The description explains the problem, the implementation, and verification steps. It is focused and mostly complete, although it does not use the template headings or include the checklist explicitly.
Linked Issues check	✅ Passed	The changes satisfy issue #10928 by forwarding the persisted model selection during restart reconciliation and adding tests for preserved reasoning effort and Codex parameters.
Out of Scope Changes check	✅ Passed	All implementation and test changes directly support preserving model selection and reasoning effort during automatic continuation after restart. No unrelated changes are evident.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 4…

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