doc(DPA2-2881): replace old 1inch business domain

[MitkoTschimev]

Change Summary

What does this PR change?
Replace old 1inch business urls with new one

Testing & Verification

How was this tested?

• Unit tests
• Integration tests
• Manual testing (describe steps)
• Verified on staging

Risk Assessment

Risk Level:

• Low - Minor changes, no operational impact
• Medium - Moderate changes, limited impact, standard rollback available
• High - Significant changes, potential operational impact, complex rollback

---

Note

Low Risk
Low risk: changes are limited to documentation examples and an AuthError message string; no runtime behavior beyond user-facing text is altered.

Overview
Updates all Fusion SDK and WebSocket documentation examples to use the production api.1inch.com HTTP/WSS endpoints instead of api.1inch.dev.

Adjusts the AuthError message to direct users to the new token portal at https://business.1inch.com/portal.

^{Reviewed by Cursor Bugbot for commit e11bf5c. Bugbot is set up for automated code reviews on this repo. Configure here.}