refactor: add typed getHttpErrorStatus helper and PlatformError type

[dcoa]

Summary

Consolidates the scattered request error's HTTP status into one typed helper, removing the as any / @ts-ignore / lie-to-the-compiler patterns that were duplicated across the module.

What and why

• getHttpErrorStatus(error: unknown): number | undefined, which safely reads the status the auth client attaches to thrown errors.
• PlatformError interface that return the AxiosError shape.

Small clean ups

• ToastManagerContext clears pending toast-removal timers on unmount and wraps showToast/discardToast in useCallback (fixes a setState-after-unmount risk and a stale-closure in the context value).
• audit-user typed the previously-implicit-any runRevokeRole param ({ data: RevokeUserRolesRequest }).
• Remove 403 error in Save button Wizard validation, now that the permissions validation supports scope-less request and the scope list is limited to user management list.

AI use acknowledgement

Supported by Claude Code

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[codecov]

Codecov Report

❌ Patch coverage is 91.30435% with 2 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (master@e03ec4b). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
...rc/components/ToastManager/ToastManagerContext.tsx	86.66%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##             master     #171   +/-   ##
=========================================
  Coverage          ?   97.55%           
=========================================
  Files             ?       68           
  Lines             ?     1677           
  Branches          ?      404           
=========================================
  Hits              ?     1636           
  Misses            ?       41           
  Partials          ?        0           

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[bra-i-am]

LGTM!

[bra-i-am]

nit: I see that the timers are being pushed to the ref at every discardToast, but they are never deleted

[dcoa]

I added a change for this, could you validate, please?