Fix CLI reference generation

[bfops]

Description of Changes

Add back the instructions for regenerating CLI docs, which were removed in #3343. I also made a script for it.

This also fixes the CI checking this file, which was silently broken in the same PR.

I have not verified that this works in Git Bash in Windows.

API and ABI breaking changes

None

Expected complexity level and risk

1

Testing

• CI passes
• CI fails if I change the CLI reference
• CLI reference looks visually reasonable on a local pnpm dev

[jdetter]

Looks good to me, I tested this on windows via git bash:

boppy@geralt MINGW64 ~/clockwork/SpacetimeDB (bfops/pnpm-install-instruction)
$ cd docs/

boppy@geralt MINGW64 ~/clockwork/SpacetimeDB/docs (bfops/pnpm-install-instruction)
$ ./scripts/generate-cli-docs.mjs

And it seemed to update the line endings in the cli reference file:

boppy@geralt MINGW64 ~/clockwork/SpacetimeDB/docs (bfops/pnpm-install-instruction)
$ git status
On branch bfops/pnpm-install-instruction
Your branch is up to date with 'origin/bfops/pnpm-install-instruction'.

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
        modified:   docs/00500-cli-reference/00100-cli-reference.md

When I add the file the changes go away which is expected. Thanks Zeke 👍