chore: Import schema and base types from @bids/schema/.

[effigies]

I updated the jsr-dist branch so that schema can be imported without caring that it's JSON: https://github.com/bids-standard/bids-specification/blob/jsr-dist/mod.ts

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.58%. Comparing base (c7d75d2) to head (dbd95d2).
Report is 4 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2115      +/-   ##
==========================================
+ Coverage   85.69%   87.58%   +1.88%     
==========================================
  Files          91      133      +42     
  Lines        3782     6973    +3191     
  Branches     1220     1656     +436     
==========================================
+ Hits         3241     6107    +2866     
- Misses        455      771     +316     
- Partials       86       95       +9     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.