fix(sagemaker): improve SSH configuration error handling for SageMakare remote connections

[bhavya2109sharma]

Problem

When attempting to connect to a SageMaker Space, if the user's SSH config has syntax errors (even outside the sm_* section), users would see a cryptic error message:

ssh check against host failed: 255

This error message:
Didn't explain what was wrong
Didn't indicate it was an SSH config issue
Didn't provide a way to fix the problem

Solution

Enhanced the SSH configuration error handling to provide a better user experience:

Shows a clear message explaining the issue.
Displays the actual SSH error (including line numbers)
Provides an "Open SSH Config" button to directly open the config file for editing

Screen.Recording.2025-11-19.at.3.43.38.PM.mov

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