Fix CI failures: lint warning, coverage gaps, and security audit

[Copilot]

CI was failing on three checks: ESLint warning, coverage thresholds not met (98.03% statements vs 99% required, 94.92% branches vs 95% required, 98.5% functions vs 100% required), and security audit.

Changes

• Lint: Removed unused Platform import from SearchBar.tsx

• Coverage: Added missing tests for storage layer edge cases

  • secureStore.ts: Memory store fallback for deleteItem
  • vaultStorage.ts: Key management functions (getOrCreateVaultKey, getVaultKey, deleteVaultKey) and export validation (empty passphrase, empty blob content, iOS iterations)

• Security: Updated @isaacs/brace-expansion to patch high-severity vulnerability

Coverage Results

All files          |   99.84 |    97.14 |     100 |   99.84
 storage           |     100 |      100 |     100 |     100
  secureStore.ts   |     100 |      100 |     100 |     100
  vaultStorage.ts  |     100 |      100 |     100 |     100

196 tests passing (8 new test cases added).

Original prompt

Fix the test cases.

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[Copilot]

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

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