allow quickly editing docs pages with keyboard shortcut: `.`

**Is your feature request related to a problem? Please describe.**
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Similar to how the keyboard shortcut for `.` works in GitHub, apply similar functionality to docs pages to enable quickly editing the page

**Describe the solution you'd like**
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- `.` uses the same functionality as "edit"
- (optional bonus) `.` uses _similar_ functionality to "edit" but opens `github.dev` instead

**Describe alternatives you've considered**
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n/a

**Additional context**
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No files, tests, or entry points are named in the issue. Start by locating the docs page edit control and any existing keyboard-shortcut handling, then compare the current Edit action with the requested `.` behavior. Done means pressing `.` on a docs page reliably opens the page for editing, with the requested GitHub-style behavior verified.

Written by the indexing model from the issue text.