[WebGPU] Add support for filterable 32-bit float textures ("float32-filterable" feature)

[chrisdavidmills]

See https://developer.chrome.com/blog/new-in-webgpu-119#filterable_32-bit_float_textures for change description.

Acceptance criteria

• Add a note to https://developer.mozilla.org/en-US/docs/Web/API/GPUDevice/createSampler#magfilter explaining that the "float32-filterable" feature must be requested for the GPUDevice if you want to filter GPUTextures with "r32float", "rg32float", and "rgba32float" formats.
• Add a BCD data point for this change (to GPUSupportedFeatures) — this shipped in Chrome 119.

[chrisdavidmills]

Content PR: #36398

[chrisdavidmills]

BCD PR: mdn/browser-compat-data#24760