fix(survey): Show error when survey name is empty in survey creation

[lshaowei18]

Problem

When creating a survey, there is no visual feedback when the saving fails because the survey name is empty:

Screen.Recording.2025-12-07.at.9.47.40.AM.mov

Changes

Screen.Recording.2025-12-07.at.9.44.38.AM.mov

How did you test this code?

1. Go to survey creation and choose start from scratch with a blank survey
2. Click on save as draft
3. You should see the error Please enter a name

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Changelog: (features only) Is this feature complete?

[greptile-apps]

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[adboio]

i literally just tried to save a survey with no name ~60 seconds ago, came to github to create an issue, and here's your PR!!

amazing timing, thank you 🙏