feat: add BlaxelAPIError base exception for unified error handling

[devin-ai-integration]

Summary

Introduces a common BlaxelAPIError base exception so users can catch all Blaxel API errors with a single except clause:

from blaxel.core import BlaxelAPIError

try:
    sandbox = await SandboxInstance.create(...)
except BlaxelAPIError as e:
    print(e.status_code, e.error_code)

Changes

• BlaxelAPIError base class in src/blaxel/core/client/errors.py with status_code, error_code, and response fields.
• UnexpectedStatus now extends BlaxelAPIError (maps status_code).
• SandboxAPIError now extends BlaxelAPIError (maps code → error_code).
• DriveAPIError now extends BlaxelAPIError (maps code → error_code).
• VolumeAPIError now extends BlaxelAPIError (maps code → error_code).
• ResponseError now extends BlaxelAPIError (extracts status_code from response).
• error_to_exception() utility function to convert the auto-generated Error data model to a BlaxelAPIError (avoids editing generated code).
• Both BlaxelAPIError and error_to_exception are exported from blaxel.core.

Backward compatibility

All existing subclass names and signatures are preserved. The only change is their parent class (Exception → BlaxelAPIError → Exception), so existing except SandboxAPIError etc. still work.

Review & Testing Checklist for Human

• Verify except BlaxelAPIError catches SandboxAPIError, DriveAPIError, VolumeAPIError, UnexpectedStatus, and ResponseError as expected
• Confirm subclass code attribute is still accessible (backward compat) alongside the new error_code on the base
• Run integration tests (uv run pytest tests/integration/ -v -s) to validate no regressions

Notes

• The Error data model in client/models/error.py is auto-generated and was not modified. Instead, a free function error_to_exception() converts it to a BlaxelAPIError.
• The sandbox client's UnexpectedStatus (sandbox/client/errors.py) is also auto-generated and was left unchanged.

Link to Devin session: https://app.devin.ai/sessions/7413077191c34b82b10658a946cc1918
Requested by: @Joffref

---

Note

Introduces BlaxelAPIError as a common base exception for all Blaxel API error types (UnexpectedStatus, SandboxAPIError, DriveAPIError, VolumeAPIError, ResponseError), plus an error_to_exception() utility to convert the auto-generated Error model. Both are exported from blaxel.core.

^{Written by Mendral for commit 62a3e67.}

[devin-ai-integration]

🤖 Devin AI Engineer

I'll be helping with this pull request! Here's what you should know:

✅ I will automatically:

• Address comments on this PR that start with 'DevinAI' or '@devin'.
• Look at CI failures and help fix them

Note: I can only respond to comments from users who have write access to this repository.

⚙️ Control Options:

• Disable automatic comment and CI monitoring

[mendral-app]

LGTM

Clean, focused change with no security issues, correctness bugs, or data loss risks. Backward compatibility is preserved — subclass code attributes are retained and existing except SandboxAPIError etc. still work. The error_to_exception() message fallback (error.message → error.error) is correct given error.error is a required str field.

_{Tag @mendral-app with feedback or questions. View session}