Repins the OCCTSwift floor to v3.0.0.
No source change of any kind. This package reads a bounding box off no OCCT type at all: nothing in Sources/ names Shape, Face, Edge or Wire, and its entire contact surface with OCCT topology is one test line calling Shape.sphere(radius:) then .mesh(...).
All 40 grep candidates for the Optional-bounds change resolved to non-OCCT types: this package's own MeshContour.bounds (which returns a non-Optional 2D pair computed from the contour's own points) and .center/.size struct fields inside the vendored meshoptimizer C++.
The other two v3.0.0 breaks have zero hits here, and zero across the ecosystem.
Verification: swift build clean, 133 tests in 24 suites passing, resolved against real v3.0.0 source. The test target was compiled and run, not just the library, which matters on this migration: swift build alone does not compile test targets.
Also corrects two stale doc references found while filing: README.md claimed OCCTSwift v1.15.10, and CLAUDE.md still cited from: "0.156.0".
Part of the ecosystem-wide v3.0.0 fanout, ecosystem#39.