docs: Update README for the repository itself r/1669

Adds a lot more information about what is actually going on here, as
well as links to relevant things such as our Monorepo document.

I'm aware that I didn't make all `//...` links clickable, but I
realised at some point that it might be easier to just update cheddar
to support highlighting those natively :-)

Change-Id: Icbb212a6c07a5cf38ab8e65d83a64bec783eb8d0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1768
Tested-by: BuildkiteCI
Reviewed-by: isomer <isomer@tvl.fyi>
Reviewed-by: kanepyork <rikingcoding@gmail.com>

0 files changed, 0 insertions, 0 deletions