port 2V2-d.2: Granny runtime on libgr2, main character model animates

Implement the Granny SDK 2.11 API the client uses on top of libgr2
(platform/EterGrnLib/GrannyRuntime.cpp, shim granny.h declared from the
SDK header): file sections, type-definition vertex conversion, material
textures by Usage, mesh/bone bindings, deformer, control clock/loop/ease
and weighted SRT sampling. Port EterGrnLib (LODController, Material, Mesh,
Model, ModelInstance*, Motion, Thing, ThingInstance, Util) plus EterLib
GrpObjectInstance/GrpCollisionObject/CollisionData verbatim and drop their
platform skeletons and pending stand-ins; register the gr2 resource
factory; vertex/index buffers are CPU-side until the 2V2-e render adapter.

app.UpdateGame/RenderGame now run 40250's bodies, reaching the
CPythonApplication members through their singletons (the platform has no
app object); CPythonGraphic joins GameSingletons in member order, and
GetMousePosition reads the host cursor.

port.login_flow asserts the main instance's PART_MAIN model has meshes,
its diffuse image loaded and the WAIT motion moves the bones between
frames; offline and live pass, port_gate macos PASS.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libgr2/tests/animation.cpp

@@ -2,6 +2,7 @@
 
 #include <cmath>
 #include <cstdio>
+#include <vector>
 
 int main() {
 	// ScaleShearCurve uses 9 values per control point. A quadratic span reads
@@ -24,5 +25,32 @@ int main() {
 			return 1;
 		}
 	}
+
+	// BoneTrack::sample fills SRT components and flags; sample_local = compose(sample).
+	gr2::BoneTrack track;
+	track.position.degree = 1;
+	track.position.dim = 3;
+	track.position.knots = {0.0f, 1.0f};
+	track.position.controls = {0.0f, 0.0f, 0.0f, 2.0f, 4.0f, 6.0f};
+	track.orientation.degree = 0;
+	track.orientation.dim = 4;
+	track.orientation.knots = {0.0f};
+	track.orientation.controls = {0.0f, 0.0f, 0.70710678f, 0.70710678f}; // 90 deg about Z
+	gr2::Transform x;
+	track.sample(0.5f, x);
+	if (x.flags != 3 || std::fabs(x.position[0] - 1.0f) > 1e-5f || std::fabs(x.position[2] - 3.0f) > 1e-5f) {
+		std::fprintf(stderr, "BoneTrack::sample flags=%u pos=%f,%f,%f\n", x.flags, x.position[0], x.position[1], x.position[2]);
+		return 1;
+	}
+	gr2::Animation anim;
+	anim.tracks.push_back(track);
+	std::vector<gr2::Mat4> local;
+	anim.sample_local(0.5f, local);
+	const gr2::Mat4 m = gr2::compose(x);
+	// Row-major composite: row 0 is the rotated X axis (0,1,0); translation in 12..14.
+	if (local.size() != 1 || local[0] != m || std::fabs(m[1] - 1.0f) > 1e-5f || std::fabs(m[12] - 1.0f) > 1e-5f) {
+		std::fprintf(stderr, "compose mismatch m[1]=%f m[12]=%f\n", m[1], m[12]);
+		return 1;
+	}
 	return 0;
 }