fix: add ConnectError to embedding retry exceptions

[S-A-D-4]

Summary

• Added httpx.ConnectError to the retry exception list in the embedding adapter
• This fixes an issue where transient network connectivity errors (TLS handshake failures, proxy connection issues) would cause immediate failure instead of retry

Problem

When creating a knowledge base, the embedding process would occasionally fail with httpx.ConnectError. The retry mechanism only caught timeout errors (ReadTimeout, ConnectTimeout, PoolTimeout) but not ConnectError, which occurs during TLS handshake failures or proxy connection issues.

Solution

Added httpx.ConnectError to the exception tuple in the retry handler, ensuring that transient connection errors are retried with exponential backoff (up to 5 retries).

Testing

• Verified that embedding requests work correctly with the change
• Tested both direct connection and proxy scenarios
• Confirmed retry behavior works as expected