[MOBILE-001] Improve mobile tap targets and popover fit

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Outline

Summary

Mobile product pass at 375px across discovery, profile editor, settings, saved, and public profile. Layouts were already clean (no horizontal overflow anywhere); the fixes address the small tap targets found in the audit and the notifications popover exceeding the viewport width.

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Changes & Enhancements

• Type of Change:
  • Feature
  • Bugfix
  • Refactor
  • Chore
• Changes:
  • (Navbar):
    • Inbox trigger hit area grows from 24x24 to 40x40 via padding with negative margin, no visual change.
    • Language switcher gains an invisible 8px hit-area extension on both sides.
    • Notifications popover is capped at the viewport width (was fixed 420px on a 375px screen).
  • (Discovery cards):
    • Card menu button gains an invisible 8px hit-area ring (26x26 visual, 42x42 touch).
    • Copy username and country/time rows grow from 16px to 32px tap height via padding with negative margin.

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Page / App Changes

Affected Next.js Routes (Local):

• /[lang] (card and navbar tap targets, inbox popover fit)
• /[lang]/u/[id] (card tap targets)

Before (Screenshot)

After (Screenshot)

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Component / Storybook Changes

Affected Storybook Components (Local):

• Discovery/ProfileCard > Free Sky

Before (Screenshot)

After (Screenshot)

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Not Doing

• Language and tag pills stay at their designed 22 to 26px height: they sit in dense rows where invisible hit-area extensions would overlap each other.

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Other (Remarks)

Audited at 375x812: no horizontal overflow on any core route, popovers fit the viewport, and the sticky save bars do not cover form content. Verified tap-target sizes and the popover fit in the browser after the fixes.

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Checklists

• Code is well-documented (comments, JSDoc, etc.).
• Existing comments were updated as needed.
• No out-of-scope changes are included.
• Write TODO comments where future work is required.
• Removed unnecessary debug code (e.g., console.log, debugger).
• Self-reviewed and tested locally.