[TypeScript] Harden API response error handling

[cwjcwj95]

This PR hardens the API response error handling in :

Problems fixed:

1. Non-2xx HTTP responses (4xx/5xx) were parsed as successful data
2. Error interceptors for 401/429 were never reliably exercised because HTTP errors never reached them
3. Callers had to duplicate status checks
4. Structured error payload details were lost

Changes:

• now checks and throws for non-2xx status codes
• Error payloads are preserved with helper
• User-friendly suggestions added via for common status codes
• Response interceptors now only receive successful responses
• Error interceptors reliably handle 401 (auth refresh trigger) and 429 (rate limit)
• Added dispatch on 401 for UI login redirect

Closes #1