Remove index.html from repository and add to .gitignore (#66)

* Initial plan

* Remove index.html and add to .gitignore

Co-authored-by: simonw <9599+simonw@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: simonw <9599+simonw@users.noreply.github.com>

Author: Copilot

.gitignore

@@ -1,3 +1,4 @@
 tools.json
 gathered_links.json
 colophon.html
+index.html