* docs: remove obsolete CodeSandbox contribution workflow
https://codesandbox.io/p/github/excalidraw/excalidraw (forking the
whole repo as an editable sandbox to submit PRs from) no longer works.
It was documented in two places — the Contributing guide and the
Development guide — as an alternative to the manual clone/fork setup.
This doesn't touch the other CodeSandbox links in the docs (README,
installation/integration/development guides for the @excalidraw/excalidraw
package), which point at the separate with-script-in-browser usage example
and are unrelated to this contribution workflow.
* chore: trigger CI
Claude Opus 5.5 (low)
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Co-authored-by: dwelle <5153846+dwelle@users.noreply.github.com>
