Resolve settings viewport before first client render

[open-inspect]

Summary

• Resolve the real media-query snapshot before the first client render, while exposing an unknown viewport during SSR and hydration.
• Let the settings shell use that readiness directly instead of a separate mount effect or synthetic hydration store. Preserve the existing boolean media-query API for other consumers.
• Remove the warning-row key changes: the rows are stateless, and presentation-derived keys introduce collisions without a demonstrated UI regression to fix. Warning identity changes are not part of this PR.

Review feedback addressed

• Fresh mobile client navigation no longer mounts the desktop settings tree before switching to mobile. The regression test uses the real media-query hook, not a resolved-value hook mock.
• The content-derived warning keys and speculative reorder test have been removed completely.

Validation

• Built @open-inspect/shared and passed web typecheck.
• Scoped ESLint and Prettier checks passed; git diff --check passed.
• 25 tests passed across the settings shell, media-query hook, sidebar layout, session sidebar, and model selector.
• Real renderToString / hydrateRoot test preserves the server busy placeholder, renders only the mobile child tree after hydration, and reports no recoverable hydration errors.
• Query switching, viewport-change subscriptions, listener cleanup, and the existing boolean SSR fallback are covered.
• Controlled comparison with current main: the fresh-client test records mount, update (the busy placeholder adds a commit). With this change it records only mount.
• Controlled comparison with the original PR head: the same test records desktop then mobile; the corrected implementation records mobile only. Both baseline checks failed as expected, and all eight final lifecycle tests passed after restoring the corrected sources.

The prior React Doctor diagnostic counts are not claimed for this narrowed revision. CI must pass on the final head before merge.

[github-actions]

Terraform Validation Results

Step	Status
Format	✅
Init	✅
Validate	✅
Tests	✅

Note: Terraform plan was skipped because secrets are not configured. This is expected for external contributors. See docs/GETTING_STARTED.md for setup instructions.

Pushed by: @open-inspect[bot], Action: pull_request

[open-inspect]

Deep review

Two blocking design issues remain. The hydration replacement changes fresh client-navigation behavior on mobile, and the warning-key change still does not provide a unique identity even though the persistence layer already has one. No changed file crosses 1,000 lines; the largest resulting source file is 471 lines.

This is submitted as a comment review rather than REQUEST_CHANGES because the authenticated GitHub App is also the pull request author, and GitHub does not permit authors to request changes on their own pull requests.

[github-actions]

Terraform Validation Results

Step	Status
Format	✅
Init	✅
Validate	✅
Tests	✅

Note: Terraform plan was skipped because secrets are not configured. This is expected for external contributors. See docs/GETTING_STARTED.md for setup instructions.

Pushed by: @ColeMurray, Action: pull_request

[ColeMurray]

Reviewed exact head 0aad072, final settings/media-query implementation and tests, existing consumers, and all review threads. Both findings are addressed and resolved: fresh mobile navigation uses the real viewport immediately without mounting desktop content, and speculative warning-key changes were removed. Controlled baseline/original-PR comparisons demonstrate the actual rendering benefit. Twenty-five focused tests, real SSR hydration, shared build, web typecheck and scoped lint/format passed. All final-head CI is green with intentional Terraform deployment skips. No remaining blockers.