feat(noise-removal): SOTA noise removal with 4 quality tiers (#57)

* feat(noise-removal): register tool in shared constants and i18n

* feat(noise-removal): add SCUNet and NAFNet model architectures

* feat(noise-removal): add Python denoising engine with 4 quality tiers

* feat(noise-removal): add TypeScript bridge for Python sidecar

* feat(noise-removal): add frontend settings with 4-tier selector

* feat(noise-removal): register in tool registry and pipeline

* feat(noise-removal): add Fastify API route with Zod validation

* feat(noise-removal): add SCUNet and NAFNet model downloads to Docker build

* test(noise-removal): add to e2e tool page rendering tests

* test(noise-removal): add integration tests for API endpoint

* style: fix biome formatting and import ordering

* fix(noise-removal): use correct model download URLs

NAFNet model is hosted on HuggingFace, not GitHub releases.
Also align SCUNet URL to use the KAIR releases (same as Docker build).

* fix(noise-removal): remove emojis from tier selector, simplify labels

Drop emoji icons from Quick/Balanced/Quality/Maximum buttons. Replace
technical algorithm names with plain descriptions users can understand.

---------

Co-authored-by: stirling-image <stirling-image@users.noreply.github.com>

packages/ai/src/index.ts

@@ -4,6 +4,7 @@ export { colorize } from "./colorization.js";
 export type { DetectFacesResult, FaceRegion } from "./face-detection.js";
 export { blurFaces, detectFaces } from "./face-detection.js";
 export { inpaint } from "./inpainting.js";
+export { noiseRemoval } from "./noise-removal.js";
 export { extractText } from "./ocr.js";
 export { seamCarve } from "./seam-carving.js";
 export { upscale } from "./upscaling.js";

packages/ai/src/noise-removal.ts

@@ -0,0 +1,52 @@
+import { readFile, writeFile } from "node:fs/promises";
+import { join } from "node:path";
+import { type ProgressCallback, runPythonWithProgress } from "./bridge.js";
+
+export interface NoiseRemovalOptions {
+  tier?: string;
+  strength?: number;
+  detailPreservation?: number;
+  colorNoise?: number;
+  format?: string;
+  quality?: number;
+}
+
+export interface NoiseRemovalResult {
+  buffer: Buffer;
+  width: number;
+  height: number;
+  format: string;
+  tier: string;
+}
+
+export async function noiseRemoval(
+  inputBuffer: Buffer,
+  outputDir: string,
+  options: NoiseRemovalOptions = {},
+  onProgress?: ProgressCallback,
+): Promise<NoiseRemovalResult> {
+  const inputPath = join(outputDir, "input_denoise.png");
+  const outputPath = join(outputDir, "output_denoise.png");
+
+  await writeFile(inputPath, inputBuffer);
+  const { stdout } = await runPythonWithProgress(
+    "noise_removal.py",
+    [inputPath, outputPath, JSON.stringify(options)],
+    { onProgress },
+  );
+
+  const result = JSON.parse(stdout);
+  if (!result.success) {
+    throw new Error(result.error || "Noise removal failed");
+  }
+
+  const actualOutputPath = result.output_path || outputPath;
+  const buffer = await readFile(actualOutputPath);
+  return {
+    buffer,
+    width: result.width,
+    height: result.height,
+    format: result.format ?? "png",
+    tier: result.tier ?? options.tier ?? "balanced",
+  };
+}