fix(tasks): reset Add Task dialog form fields on close

[ShivaGupta-14]

Description

• Added form reset logic in useEffect when dialog closes.
• Clears description, priority, project, due, tags, and tagInput states.
• Ensures clean form state when reopening Add Task dialog after cancel.

Additional Changes

• Fixed col-span-3 styling by wrapping Input components in wrapper div
• Added "None" option to priority dropdown
• Renamed priority options for better clarity: High (H), Medium (M), Low (L)

Fixes: #277

Checklist

• Ran npx prettier --write . (for formatting)
• Ran gofmt -w . (for Go backend)
• Ran npm test (for JS/TS testing)
• Added unit tests, if applicable
• Verified all tests pass
• Updated documentation, if needed

Additional Notes

Self-Review

I've reviewed my changes and confirm:

• All tests pass locally
• Code follows existing test patterns in the project
• Form reset works correctly on Cancel button click or clicking outside the dialog
• Input field styling is now consistent across the dialog
• No breaking changes to existing functionality

Video

Screen.Recording.2025-12-14.at.7.00.47.AM.mov

[github-actions]

Thank you for opening this PR!

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[ShivaGupta-14]

@its-me-abhishek, I’ve already completed the self-review and added it to the PR.