chore: add legacy docs redirects and some minor fixes

[maribethb]

The basics

• I validated my changes

The details

Resolves

Fixes more docs things

Proposed Changes

• Adds some legacy redirects that devsite used to be doing.
  • got the list of all the legacy redirects from devsite as yaml
  • cleaned up and removed some that no longer apply (e.g. we no longer have an ios codelab so just removed it)
  • removed some from ancient docs refactoring. if someone has a bookmark from 2016 they're gonna need to update it. trying to balance backwards compatibility with keeping a maintainable redirects file.
  • made ai convert the cleaned up yaml to the redirects format that cloudflare uses
  • had ai check for any docs pages that didn't actually exist and link to the correct page. also had it correct anything that required "chaining" multiple redirects because i don't think cf does that.
• removed the web/ part of the configure/web docs which was leftover from when we used to have android and ios directories, then added a wildcard redirect for that and fixed any of the hardcoded redirects
• replaced embedded youtube with link to video because embedding yt might introduce google cookies and we don't have a cookie consent bar on this site i think
• misc fix i threw in here, sorry, there were some broken images in the developer tools doc. ai said there weren't any others like this.

Reason for Changes

getting docs site ready to launch

Test Coverage

tested locally (can't test redirects tho)

Documentation

Additional Information