Summary

Follow-up to #8612. Another docs-only pass fixing objectively-wrong JSDoc and comment issues across the engine. No runtime behaviour changes.

Duplicate-word typos (14 sites)

Each is a one-word fix inside a JSDoc or shader-source comment line:

• src/core/math/mat4.js — "the the matrix"
• src/framework/bundle/bundle.js — "to to DataView"
• src/framework/components/layout-group/component.js — "will be be rendered"
• src/framework/xr/xr-anchor.js — "has has been persisted" (public @event)
• src/platform/graphics/dynamic-buffers.js — "staging to to the GPU buffer"
• src/platform/graphics/texture.js — "3 formats formats"
• src/platform/graphics/uniform-buffer-format.js — "layout of of data"
• src/platform/graphics/webgpu/webgpu-dynamic-buffers.js — "in the the command buffer"
• src/scene/graphics/post-effect.js — "take a a render target"
• src/scene/materials/standard-material.js (x2) — "will be be multiplied" on refractionVertexColor and thicknessVertexColor props
• src/scene/shader-lib/programs/standard.js — "to to replace"
• src/scene/shader-lib/glsl/chunks/render-pass/frag/sampleCatmullRom.js and its WGSL twin — "sample a a 4x4 grid" in shader source comments

Broken {@link} cross-reference

• src/extras/gizmo/rotate-gizmo.js (2 sites) — @deprecated Use {@link RotationGizmo#rotationMode}. The class is RotateGizmo; RotationGizmo does not exist anywhere in src/. Fixed to {@link RotateGizmo#rotationMode}.

Missing word in applyForce description

• src/framework/components/rigid-body/component.js (2 overload blocks) — "the force can be applied at an offset this point..." -> "...at an offset from this point...".

Incomplete @returns type

• src/scene/mesh-instance.js — MeshInstance#getParameter returns this.parameters[name], which is undefined when the key is missing. Documented @returns {object} -> @returns {object|undefined} with a matching description. This mirrors the Compute#getParameter fix already merged in docs: fix incorrect JSDoc in public APIs #8612.

Public API changes

Only JSDoc changes; no runtime signatures change. One documented return type is widened:

Before:

/**
 * @returns {object} The named parameter.
 */
getParameter(name) { ... }

After:

/**
 * @returns {object|undefined} The named parameter, or `undefined` if no parameter with that
 * name is set on this mesh instance.
 */
getParameter(name) { ... }

Test plan

• npx eslint on all 16 touched files passes.
• No behavioural code changes; nothing else to test.