FCE-3061: SDK reconnect should handle invalid token

[MiloszFilimowski]

Description

• packages/ts-client/src/reconnection.ts: If a socketClose carries an auth or join error while a reconnect is in progress, clear the scheduled reconnect, set status to error, and stop retrying (still ignores those closes when idle).
• packages/ts-client/src/auth.ts: isAuthError matches case-insensitively and treats known reasons as substrings so server messages like Invalid token are detected reliably.
• packages/react-client/src/hooks/internal/useReconnection.ts: On authError / joinError, move reconnection UI to error only when status was already reconnecting.
• packages/ts-client/src/tests/: Added auth.test.ts and reconnection.test.ts (Vitest) for the above behavior.

Motivation and Context

Reconnection could keep retrying or show the wrong status when the socket closed with auth/join failures, especially if the close reason casing did not match the client’s exact strings. This aligns core and React reconnection state with those terminal failures.

Documentation impact

• Documentation update required
• Documentation updated in another PR
• No documentation update required

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to
  not work as expected)

[linear]

FCE-3061 SDK reconnect should handle invalid token

FCE-3060 Reconnections should happen based on mobile internet status

[Copilot]

Pull request overview

This PR adjusts reconnection behavior in the TS client and React client so that terminal auth/join failures stop an in-progress reconnect cycle, and improves auth-error detection to be case-insensitive/substring-based, with accompanying Vitest coverage.

Changes:

• TS client: stop scheduled reconnects and transition to an error state when an auth/join socket close happens during active reconnection.
• TS client: make isAuthError detection case-insensitive and substring-based; add tests for auth and reconnection behavior.
• React client: update useReconnection to move UI to "error" on authError/joinError only if already "reconnecting".

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/ts-client/src/reconnection.ts	Cancels pending reconnect + sets error state when auth/join close occurs during reconnection.
packages/ts-client/src/auth.ts	Updates auth error detection logic to be case-insensitive/substring-based.
packages/react-client/src/hooks/internal/useReconnection.ts	Adjusts reconnection UI state transitions for auth/join errors.
packages/ts-client/src/tests/auth.test.ts	Adds Vitest coverage for isAuthError matching behavior.
packages/ts-client/src/tests/reconnection.test.ts	Adds Vitest coverage for stopping reconnection on auth/join errors mid-reconnect.

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[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 4 comments.

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