Add link pasting

[riasvdv]

Adds default-on link paste support, which is a useful feature GitHub's markdown editor has.

Pasting a safe absolute URL over selected text now wraps the selection as a Markdown link.

The behavior can be disabled with linkPaste: false, data-ot-link-paste="false", or web component link-paste="false". Ctrl/Cmd+Shift+V bypasses formatting for the next paste. The URL allowlist is shared with the parser sanitizer, including tel: and sms: support.

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Summary by cubic

Adds default-on link paste: pasting a safe URL over selected text wraps it as a Markdown link, matching GitHub’s editor. Uses the parser’s safe URL allowlist (now includes tel: and sms:) and supports a one-time bypass with Ctrl/Cmd+Shift+V.

• New Features
  • Wraps selected text on paste of safe absolute URLs; no selection keeps the paste native.
  • Disable via linkPaste: false, data-ot-link-paste="false", or web component link-paste="false"; supports reinit and attribute updates.
  • Shares sanitizer allowlist with the parser, including tel: and sms:.
  • File pastes still go to file upload (take precedence over link wrapping).
  • Updated docs, types, and tests (test/link-paste.test.js); README size updated to ~119KB; test script includes the new test.

^{Written for commit a1e095c. Summary will update on new commits.}