Expand Storybook story coverage beyond the current components

[nanaf6203-bit]

Context

Storybook is configured (with a11y addon and vitest integration in vitest.config.ts), but stories exist for only ~16 components; critical UI (PropertyCard variants, FilterSidebar, WalletModal, NotificationCenter) lacks stories.

Problem

Design review, a11y addon checks, and visual regression have limited surface; component changes rely solely on app-level e2e.

Proposed approach

Add stories for the highest-traffic components with states (loading/error/empty, RTL), enable test-storybook in CI, and track coverage.

Acceptance criteria

• Stories added for priority components
• npm run storybook displays them with a11y panel
• CI job builds/tests Storybook

[eulami]

@eulami has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi. Kindly assign me to fix this issue

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Congratulations, @eulami! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

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[drips-wave]

This issue has been completed by @eulami as part of the Stellar Wave Program's 9th Wave 🥳

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