add transform forest snapshot tests

Author: Wumpf

Cargo.lock

@@ -9568,6 +9568,7 @@ dependencies = [
  "ahash",
  "bitflags 2.9.4",
  "glam",
+ "insta",
  "itertools 0.14.0",
  "nohash-hasher",
  "re_chunk_store",

crates/store/re_tf/Cargo.toml

@@ -34,3 +34,6 @@ itertools.workspace = true
 nohash-hasher.workspace = true
 thiserror.workspace = true
 vec1 = { workspace = true, features = ["smallvec-v1"] }
+
+[dev-dependencies]
+insta.workspace = true

crates/store/re_tf/src/snapshots/re_tf__transform_forest__tests__simple_entity_hierarchy__root_info_pinhole.snap

@@ -0,0 +1,71 @@
+---
+source: crates/store/re_tf/src/transform_forest.rs
+expression: "pretty_print_enity_path_hashes_in(transform_forest.root_info(EntityPath::from(\"top/pinhole\").hash()),\n&all_entity_paths)"
+---
+Some(
+    Pinhole(
+        PinholeTreeRoot {
+            parent_tree_root: /,
+            pinhole_projection: ResolvedPinholeProjection {
+                image_from_camera: PinholeProjection(
+                    Mat3x3(
+                        [
+                            1.0,
+                            0.0,
+                            0.0,
+                            0.0,
+                            2.0,
+                            0.0,
+                            50.0,
+                            100.0,
+                            1.0,
+                        ],
+                    ),
+                ),
+                resolution: Some(
+                    Resolution(
+                        Vec2D(
+                            [
+                                100.0,
+                                200.0,
+                            ],
+                        ),
+                    ),
+                ),
+                view_coordinates: ViewCoordinates(
+                    ViewCoordinates(
+                        [
+                            3,
+                            2,
+                            5,
+                        ],
+                    ),
+                ),
+            },
+            parent_root_from_pinhole_root: Affine3A {
+                matrix3: Mat3A {
+                    x_axis: Vec3A(
+                        1.0,
+                        0.0,
+                        0.0,
+                    ),
+                    y_axis: Vec3A(
+                        0.0,
+                        1.0,
+                        0.0,
+                    ),
+                    z_axis: Vec3A(
+                        0.0,
+                        0.0,
+                        1.0,
+                    ),
+                },
+                translation: Vec3A(
+                    1.0,
+                    1.0,
+                    0.0,
+                ),
+            },
+        },
+    ),
+)