[FE-84] Graceful session expiry and token refresh

[yusuftomilola]

Overview

Auth state spans middleware.ts, store/auth.store.ts, components/auth-initializer.tsx, and lib/auth-api.ts. When a token expires mid-session the user currently risks a confusing failure and losing an in-progress form.

Tasks

• Detect 401 centrally in the axios interceptor and attempt a single refresh, queueing concurrent requests until it resolves.
• On refresh failure, clear auth state and redirect to login preserving the intended destination.
• Prevent refresh stampedes — many simultaneous 401s must trigger exactly one refresh call.
• Warn before expiry with a "Stay signed in" prompt rather than dropping the session silently.
• Preserve unsaved form input across the redirect where practical.
• Synchronize logout across tabs via a storage event.

Acceptance Criteria

• An expired token refreshes transparently with no visible failure.
• Failed refresh returns the user to their original page after re-authenticating.
• Ten concurrent 401s produce exactly one refresh request (covered by a test).

Dependencies

Blocked by [FE-65]; backend refresh from [BE-80].

Notes for Contributors

Comment below to be assigned.

[AbuJulaybeeb]

@AbuJulaybeeb has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi Maintainer, haven reviewed the description of the issue, and well experienced with Js Library,
I would like to hop on the issue and sure to deliver at ETA 2hrs

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[Caneryy]

@Caneryy has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello, may I work on this issue?

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[jaymhorsh]

@jaymhorsh has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

kindly assign

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[drips-wave]

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