ruff --select UP007,UP045 --fix converted ~1760 sites across the
backend: `Optional[T]` → `T | None`, `Union[X, Y]` → `X | Y`. The
remaining module-level alias targets that ruff conservatively skips
(BindableFloatInput, ColorList, DeviceConfig) were converted by hand
earlier in the pass. black -formatted the result so the wider unions
fit cleanly under the 100-char line budget.
pyproject.toml now sets [tool.ruff.lint] extend-select = ["UP007",
"UP045"] so future legacy imports fire CI on every push. The
pre-commit ruff hook was bumped from v0.8.0 -> v0.15.12 to recognise
UP045 (split off from UP007 in v0.13).
The "static" source kind always rendered a SINGLE color and the name
confused new code paths. Rename the module + kind to "single". Storage
keeps backward-compatible serialisation. Frontend color-strip cards /
gradient / index / test modules and the affected tests follow the new
name.
Allow composite sources to reference other composite/mapped sources as
layers. Adds cycle detection (via transitive dependency graph walk),
depth limiting (MAX_COMPOSITE_DEPTH=4), and a runtime safety net in the
stream manager. Frontend layer dropdown now shows all source types
except the source being edited.
17 new tests covering cycles, depth limits, and valid nesting — all
715 tests passing.
alexei.dolgolyov