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

[Copilot]

Pull request overview

Migrates project type checking from mypy to ty across tooling, CI, documentation, and source annotations.

Changes:

• Replaces mypy dependencies and commands with ty.
• Updates annotations, tests, documentation, and development configuration.
• Fixes the .pre-commit-config.yaml hook configuration before approval.

Reviewed changes

Copilot reviewed 28 out of 30 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Summary
uv.lock	Updates locked type-checking dependencies.
tests/unit/test_schemas.py	Adds explicit test fixture typing.
tests/unit/test_llm.py	Narrows structured response typing.
tests/integration/test_tuner.py	Adds result assertions and safe callable-name access.
tests/integration/test_job_id_wiring.py	Narrows the built process type.
tests/integration/test_component_decorator.py	Adds process type narrowing.
README.md	Documents ty usage.
pyproject.toml	Replaces mypy configuration and dependency.
plugboard/utils/ray.py	Makes callable-name access type-safe.
plugboard/utils/logging.py	Improves IPython detection.
plugboard/state/state_backend.py	Adds state serialization annotations.
plugboard/library/sql_io.py	Refines SQL and async reflection typing.
plugboard/library/llm.py	Validates structured response payloads.
plugboard/events/event_handlers.py	Safely resolves method qualified names.
plugboard/connector/ray_channel.py	Updates channel signatures and annotations.
plugboard/connector/asyncio_channel.py	Updates channel message parameter naming.
plugboard/component/utils.py	Adds callable protocol typing and narrowing.
plugboard/component/component.py	Adds event-list type casts.
plugboard/__init__.py	Makes package version lookup robust.
plugboard-schemas/pyproject.toml	Removes obsolete mypy configuration.
plugboard-schemas/plugboard_schemas/_validator_registry.py	Safely formats callable names.
plugboard-schemas/plugboard_schemas/__init__.py	Makes version lookup robust.
Makefile	Runs ty during linting.
CONTRIBUTING.md	Documents ty and lint commands.
AGENTS.md	Updates type-checking guidance.
.pre-commit-config.yaml	Critical: the configured ty hook repository, revision, and ID cannot be resolved; use the matching ty-check metadata.
.gitignore	Removes mypy cache entries.
.github/workflows/lint-test.yaml	Uses ty in CI.
.github/agents/lint.agent.md	Updates lint-agent instructions.
.devcontainer/devcontainer.json	Adds the ty editor extension.

Suppressed comments (1)

plugboard/connector/ray_channel.py:56

• RayChannel is a public channel and does not call Channel.__init__, so this method is exposed directly. Renaming its parameter from item to msg makes existing keyword calls such as await channel.send(item=value) fail with TypeError; this is an API break unrelated to the type-check migration. Preserve the old keyword (or explicitly support both names) while keeping the base-method typing consistent.

    async def send(self, msg: _t.Any) -> None:
        """Sends an item through the `RayChannel`."""
        await self._actor.send.remote(msg)  # type: ignore

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