♿(frontend) focus skip link on headings and skip grid dropzone

[Ovgodd]

Purpose

Improve keyboard and screen reader navigation by moving skip link focus to page
headings instead of the whole main region, and by keeping the docs grid
dropzone out of the keyboard focus order.

Proposal

• focus the skip link and route-change target on the first available page
  heading (h1, then h2) instead of main
• remove the header logo heading semantics so each page keeps a single,
  meaningful main heading
• update main page titles to use proper heading levels for the new focus
  target
• prevent the docs grid dropzone container from receiving keyboard focus

[github-actions]

Size Change: -956 B (-0.02%)

Total Size: 4.25 MB

Filename	Size	Change
apps/impress/out/_next/static/97ff3eed/_buildManifest.js	933 B	+933 B (new file)	🆕
apps/impress/out/_next/static/ce55cc65/_buildManifest.js	0 B	-930 B (removed)	🏆

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