Add delay on submitting from welcome view

[mrubens]

Fix #990 , similar to #912

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Important

Adds a 50ms delay in handleSubmit in WelcomeView.tsx to ensure blur events complete before validating API configuration.

• Behavior:
  • Adds a 50ms delay in handleSubmit in WelcomeView.tsx to ensure blur events complete before validating API configuration.
  • Focuses the active element's parent to trigger blur before the delay.
• Misc:
  • Fixes issue OpenRouter returns 401 error with valid API key #990, similar to Make sure to blur fields when user hits Done in settings #912.

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