Support vitest watch mode

[brandonjpierce]

We currently run something similar to the following in each workspace package for the test command:

pnpm run vitest --run --dir src

The explicit --run flag prevents the --watch flag from working as it explicitly disables watch. The fix:

Update all packages/* to use the following for their test script command:

pnpm run vitest --dir=src

This way you can isolate to a package and enable watch mode for tests e.g.:

pnpm --filter=@accelint/math run test --watch