- Added incremental `pyright` type checking. A `pyrightconfig.json` at the repo root uses `typeCheckingMode: "basic"` with an explicit `include` list of modules that pass cleanly (`clocks`, `metrics`, `transcriptions`, `frames`, `observers`, `extensions`, `turns`, `pipeline`, `runner`). Remaining modules will be added in subsequent PRs. CI enforces the checked set via `uv run pyright` in the format workflow.