[ty] Ecosystem analyzer: parallelize, fix race condition (#19252)
## Summary
Pulls in two fixes and a performance optimization:
- Fix a bug with the Markdown table formatting.
- Combine the two `analyze` commands into a single `diff` command. This
means we only need to set up the projects once, which is faster and also
avoids a race condition where projects could change between the two
`analyze` runs.
