feat(Turborepo): Add support for $TURBO_DEFAULT$ to file hash watcher (#8086)
### Description
- inputs in a `HashSpec` are no longer an option, but can be default,
default with extras (`$TURBO_DEFAULT$`), or specific globs (`inputs` w/o
`$TURBO_DEFAULT$`).
- Properly invalidate `HashSpec` instances that use `$TURBO_DEFAULT$`
### Testing Instructions
Add previously-failing test for inputs that use `$TURBO_DEFAULT$`.
Closes TURBO-2988
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Co-authored-by: Greg Soltis <Greg Soltis>