Bump mypy to 2.0.0 and enable parallel checking (#3146)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: adamtheturtle

.pre-commit-config.yaml

@@ -174,7 +174,7 @@ repos:
       - id: mypy
         name: mypy
         stages: [pre-push]
-        entry: uv run --extra=dev -m mypy
+        entry: uv run --extra=dev -m mypy --num-workers=4
         language: python
         types_or: [python, toml]
         pass_filenames: false
@@ -185,7 +185,8 @@ repos:
       - id: mypy-docs
         name: mypy-docs
         stages: [pre-push]
-        entry: uv run --extra=dev doccmd --no-write-to-file --language=python --command="mypy"
+        entry: uv run --extra=dev doccmd --no-write-to-file --language=python --command="mypy
+          --num-workers=4"
         language: python
         types_or: [markdown, rst]