chore: Migrate to ty type checking

[toby-coleman]

Summary

Migrate from mypy to ty for type-checking. Significantly faster lint checks.

Changes

• Swaps output mypy and replaces with ty.
• Updated documentation.
• Updates to code where required.

[github-actions]

Benchmark comparison for 712ef942 (base) vs b03c6e2b (PR)

------------------------------------------------------------------------------------------------------------------ benchmark: 2 tests -----------------------------------------------------------------------------------------------------------------
Name (time in ms)                                                                         Min                 Max                Mean            StdDev              Median               IQR            Outliers     OPS            Rounds  Iterations
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_benchmark_process_run (main/.benchmarks/Linux-CPython-3.14-64bit/0001_base)     546.7495 (1.0)      554.8212 (1.00)     550.6825 (1.00)     3.2229 (2.21)     549.4150 (1.00)     4.7800 (2.77)          2;0  1.8159 (1.00)          5           1
test_benchmark_process_run (pr/.benchmarks/Linux-CPython-3.14-64bit/0001_pr)         548.5126 (1.00)     552.2200 (1.0)      549.8147 (1.0)      1.4561 (1.0)      549.3233 (1.0)      1.7285 (1.0)           1;0  1.8188 (1.0)           5           1
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Legend:
  Outliers: 1 Standard Deviation from Mean; 1.5 IQR (InterQuartile Range) from 1st Quartile and 3rd Quartile.
  OPS: Operations Per Second, computed as 1 / Mean

[codecov]

Codecov Report

❌ Patch coverage is 95.55556% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
plugboard/library/llm.py	33.33%	1 Missing and 1 partial ⚠️

📢 Thoughts on this report? Let us know!

[github-actions]

Benchmark comparison for 78e8f549 (base) vs 87dd8bd6 (PR)

------------------------------------------------------------------------------------------------------------------ benchmark: 2 tests -----------------------------------------------------------------------------------------------------------------
Name (time in ms)                                                                         Min                 Max                Mean            StdDev              Median               IQR            Outliers     OPS            Rounds  Iterations
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_benchmark_process_run (main/.benchmarks/Linux-CPython-3.14-64bit/0001_base)     369.9486 (1.0)      396.5094 (1.0)      382.0568 (1.0)      9.4584 (1.00)     381.1066 (1.00)     7.3778 (1.10)          2;0  2.6174 (1.0)           5           1
test_benchmark_process_run (pr/.benchmarks/Linux-CPython-3.14-64bit/0001_pr)         377.8546 (1.02)     400.0086 (1.01)     383.2194 (1.00)     9.4255 (1.0)      379.3404 (1.0)      6.6933 (1.0)           1;1  2.6095 (1.00)          5           1
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Legend:
  Outliers: 1 Standard Deviation from Mean; 1.5 IQR (InterQuartile Range) from 1st Quartile and 3rd Quartile.
  OPS: Operations Per Second, computed as 1 / Mean