fix(web): changing a project's model no longer keeps the old model's options

[yaacovcorcos]

Changing a project's model kept the previous model's options because the scoped settings planner merged complete model selections with the saved value. Project and checkout selections now replace those options while retaining omitted identity fields. This covers default, text-generation, source-control writer, and review-guide models; options-only patches retain the existing completion behavior.

Based on @yaacovcorcos's original work in #16581. Preserved the contributor commits, merged current main, and rebuilt the fix inline in the existing planner. The three original regression cases became two cases using existing fixtures.

Validation on Linux:

• Scoped settings suite: 29 passed. With main's production planner temporarily restored, the model replacement regression fails with stale options; restoring the fix passes. Final coverage includes all four model settings.
• Web-only typecheck, scoped lint/format, and whitespace checks passed.
• Running web client, isolated project: Astra at Extra High → Luna. Before: saved reasoningEffort: xhigh and serviceTier: default survive. After: saved selection has only instance/model and the picker shows Luna's configured defaults. Screenshots use the same project, viewport, and scroll position; the before capture uses the actual main planner.
• macOS, Windows, iOS, Android, and Electron desktop were not run. Desktop shares this planner; mobile's separate planner assigns selections directly. Test-data migration from the host's live database failed due to a different build's migration history, so verification used a fresh isolated project and thread.

Before — stale Extra High effort after switching to Luna:

After — Luna uses its configured defaults and no stale options are saved:

Independent review: two whole-PR rounds with Opus 5.5 and GPT-6-Sol. Round one found no production defects; its optional test-shape concern was addressed by removing synthetic casts. Round two returned no findings from either reviewer. Current-head CI passed (lint, build/typecheck, web and server tests); Macroscope approved the published head. The earlier cancelled fingerprint attempt was superseded by a successful run. Unmerged.

Implementation: GPT-6.1-Sol (high), Codex harness in T3 Code. Tests: GPT-6-Astra (high), Codex harness. Reviews: Claude Opus 5.5 and GPT-6-Sol through T3 Code.

[chatgpt-codex-connector]

You have reached your Codex usage limits for code reviews. You can see your limits in the Codex usage dashboard.
To continue using code reviews, add credits to your account and enable them for code reviews in your settings.

[macroscopeapp]

Approvability

Verdict: Approved at 9da9f7c

Macroscope's review found this PR approvable — This is a narrowly scoped project-settings bug fix that prevents stale model options from carrying across explicit model changes while preserving existing inheritance behavior. Production logic is isolated to the scoped settings planner and is covered by focused regression tests for all affected model settings.

^{You can add or adjust custom eligibility rules. Learn more.}

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

• Configuration used: Path: .coderabbit.config.ts
• Review profile: CHILL
• Plan: Advanced
• Run ID: 6644e8b2-b378-4483-a4db-26b68c314b27

📥 Commits

Reviewing files that changed from the base of the PR and between 3dfe373 and f390f1a.

📒 Files selected for processing (2)

• apps/web/src/components/settings/scopedSettings.test.ts
• apps/web/src/components/settings/scopedSettings.ts

Included review availability: This review used your included allowance. Your plan provides up to 10 included reviews per hour; 5 remain after this review.

📝 Walkthrough

The scoped settings patch planner now handles patches for three model-selection settings separately from other object-valued settings. New tests cover model replacement, model-only patches, and options-only patches.

Changes: Scoped model-selection patches

Layer / File(s)	Summary
Model-selection patch handling apps/web/src/components/settings/scopedSettings.ts, apps/web/src/components/settings/scopedSettings.test.ts	The planner preserves available effective instanceId and model values before applying a matching patch. Tests check option removal on model replacement and retention of saved selection fields for partial patches.

Priority: ➖ Normal

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

Change: Bug fix

Suggested reviewers: juliusmarminge

Merge Risk: ⚪ Minimal · up to f390f

Changing a project's model now drops the previous model's options, while partial patches still keep the saved instance or model. No merge-blocking risk is evident.

Pre-merge checks: 4

Check name	Status	Explanation
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Title check		The title clearly describes the primary fix: changing a project's model no longer preserves stale options. It uses a conventional commit format and is concise.
Description check		The description clearly explains the problem, the implementation, scope, verification results, limitations, screenshots, and agent usage. It links the related pull request for scope context, although …

Full details: Description check

Explanation

The description clearly explains the problem, the implementation, scope, verification results, limitations, screenshots, and agent usage. It links the related pull request for scope context, although it does not include an explicit maintainer approval comment.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create a new PR

• Autopilot · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

_{Comment @coderabbitai help to get the list of available commands.}

Dismissing prior approval to re-evaluate f390f1a

[juliusmarminge]

Taking over this one as maintainer for batch server-persistence-02. I will preserve the original commits, merge current main, reduce the tests to focused behavior coverage, and run independent implementation and adversarial review passes. No merge is planned.

Dismissing prior approval to re-evaluate 9da9f7c