fix: improve accessibility of number input spinner controls

[Ram-sah19]

** Description**

This pull request improves the usability and accessibility of native number input fields by making browser-provided increment/decrement spinner controls consistently visible across supported browsers and devices.

Previously, WebKit-based browsers only displayed spinner arrows when the input was hovered or focused, which reduced discoverability and negatively impacted touch-device usability.

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Problem

Native number inputs in Chromium/WebKit browsers (::-webkit-inner-spin-button and ::-webkit-outer-spin-button) default to hidden or low-opacity states until hover/focus interaction occurs.

This caused several UX issues:

• Spinner controls were invisible on touch/mobile devices where hover interactions do not exist
• Users could miss the availability of increment/decrement functionality
• Accessibility and discoverability of numeric controls were reduced

Affected areas included:

• Trim start/end inputs
• Custom width/height preset inputs
• Any shared numeric configuration field

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Solution

A lightweight global CSS enhancement was added in src/app/globals.css.

The implementation:

• Targets WebKit spin button pseudo-elements

• Forces spinner controls to remain visible using:

  opacity: 1 !important;

• Preserves native browser behavior and accessibility

• Avoids introducing custom input implementations or additional TSX logic

This keeps the solution:

• Minimal
• Maintainable
• Cross-component compatible
• Mobile-friendly

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Changes Included

• Added global visibility overrides for:

  • ::-webkit-inner-spin-button
  • ::-webkit-outer-spin-button

• Improved discoverability for:

  • Trim Controls
  • Custom Output Size inputs
  • Other reusable number inputs

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Testing

Steps to Verify

1. Run the application locally:

   npm run dev

2. Navigate to:

   • Trim controls
   • Custom video preset dimensions

3. Observe the number input fields without hovering.

Expected Result

• Spinner arrows remain visible at all times
• Inputs retain native browser functionality
• Controls are usable on desktop and mobile devices
• Accessibility and discoverability are improved

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Accessibility Impact

• Improves visibility of numeric input affordances
• Enhances mobile usability where hover is unavailable
• Preserves native keyboard and assistive technology support

---

Closes #798

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[github-actions]

👋 Thanks for your PR, @Ram-sah19!

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[github-actions]

✅ PR Format Check Passed — @Ram-sah19

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