fix(web): normalize dropdown option-filter input and option values

[yyqdbngt]

Summary

• components/InstanceSelect.tsx: extract the instance-selector filterOption into an exported matchesInstanceOption helper that coerces both the search string and the option label with String(...) ?? '' before lower-casing.
• pages/settings/AiAssistantTab.tsx: extract the two AutoComplete filterOptions (model selector + API-base preset selector) into one exported matchesAiOption helper with the same double-sided coercion; the old API-base filter additionally called .toLowerCase() on option.value without any String() guard, and all three old expressions called input.toLowerCase() unguarded.
• Add regression suites for both helpers (case-insensitive match, empty input, nullish/non-string options and input).

Why

These dropdown filters compared user input against option fields without normalizing either side: a missing search string (input.toLowerCase() on undefined) or a non-string option value ((option?.value ?? '').toLowerCase() on a number/null payload) would throw inside antd's filter path and break the whole dropdown. This is the same class of gap already fixed for the studio producer-group selector (matchesProducerGroupOption) and the component already used the one-sided String(option?.label ?? '') pattern while leaving input unguarded.

Testing

• cd web && ./node_modules/.bin/vitest run src/pages/settings/__tests__/aiAssistantOptionFilter.test.ts src/components/__tests__/instanceSelectFilter.test.ts — 2 files, 10 new tests passed.
• cd web && ./node_modules/.bin/vitest run src/pages/settings/__tests__/AiAssistantTab.test.tsx — 5 pre-existing tests still pass.
• cd web && ./node_modules/.bin/vitest run src/components — 8 files, 58 tests passed (no regressions in the shared component domain).
• cd web && ./node_modules/.bin/tsc --noEmit — clean.
• cd web && ./node_modules/.bin/eslint src/pages/settings/AiAssistantTab.tsx src/components/InstanceSelect.tsx src/pages/settings/__tests__/aiAssistantOptionFilter.test.ts src/components/__tests__/instanceSelectFilter.test.ts — 0 errors (2 react-refresh warnings for the exported helpers, same precedent as other helper exports).

[RockteMQ-AI]

Summary

This PR contains moderate changes (182 lines). I have performed an initial structural review.

Observations

• Changes appear well-scoped
• CLA status: unknown

Maintainers: please verify the implementation details match the intended behavior.

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Automated review by github-manager-bot

[RockteMQ-AI]

Summary

Defensive fix that improves input validation and error handling. Code looks clean and follows existing patterns.

LGTM

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Automated review by "github-manager-bot"

[RockteMQ-AI]

LGTM — defensive fix improving input validation and error handling.

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Automated review by "github-manager-bot"