docs: add per-tool API documentation and fix parity gaps

- Create 53 per-tool VitePress documentation pages with accurate
  parameters from Zod schemas, example requests, and response formats
- Add root llms.txt for LLM-friendly repo browsing
- Fix OpenAPI spec: add auth and 422 error schemas to
  edit-metadata/inspect and strip-metadata/inspect sub-routes
- Fix tool count inconsistency (52 -> 53) across landing site,
  e2e tests, and local docs
- Rename color-adjustments.ts to adjust-colors.ts to match tool ID
- Update VitePress sidebar with all 8 tool categories and top nav

apps/docs/tools/svg-to-raster.md

@@ -0,0 +1,78 @@
+# SVG to Raster
+
+Convert SVG files to raster image formats (PNG, JPEG, WebP, AVIF, TIFF, GIF, HEIF, or JXL) at custom resolution and DPI. Also supports batch conversion of multiple SVGs.
+
+## API Endpoint
+
+`POST /api/v1/tools/svg-to-raster`
+
+## Parameters
+
+| Parameter | Type | Required | Default | Description |
+|-----------|------|----------|---------|-------------|
+| width | integer | No | - | Target width in pixels (1 to 65536). Maintains aspect ratio if only one dimension set. |
+| height | integer | No | - | Target height in pixels (1 to 65536). Maintains aspect ratio if only one dimension set. |
+| dpi | integer | No | 300 | Render DPI, controls the base rasterization density (36 to 2400) |
+| quality | number | No | 90 | Output quality for lossy formats (1 to 100) |
+| backgroundColor | string | No | `"#00000000"` | Background color as hex (6 or 8 characters, 8-char includes alpha) |
+| outputFormat | string | No | `"png"` | Output format: `png`, `jpg`, `webp`, `avif`, `tiff`, `gif`, `heif`, `jxl` |
+
+## Example Request
+
+```bash
+curl -X POST http://localhost:13490/api/v1/tools/svg-to-raster \
+  -F "file=@logo.svg" \
+  -F 'settings={"width":1024,"dpi":300,"outputFormat":"png","backgroundColor":"#FFFFFF"}'
+```
+
+## Example Response
+
+```json
+{
+  "jobId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
+  "downloadUrl": "/api/v1/download/a1b2c3d4-e5f6-7890-abcd-ef1234567890/logo.png",
+  "previewUrl": "/api/v1/download/a1b2c3d4-e5f6-7890-abcd-ef1234567890/preview.webp",
+  "originalSize": 12345,
+  "processedSize": 67890
+}
+```
+
+## Batch Endpoint
+
+`POST /api/v1/tools/svg-to-raster/batch`
+
+Convert multiple SVG files in one request. Returns a ZIP archive.
+
+### Additional Batch Parameters
+
+| Parameter | Type | Required | Default | Description |
+|-----------|------|----------|---------|-------------|
+| clientJobId | string | No | - | Optional client-provided job ID for progress tracking (max 128 chars) |
+
+### Batch Example Request
+
+```bash
+curl -X POST http://localhost:13490/api/v1/tools/svg-to-raster/batch \
+  -F "file=@icon1.svg" \
+  -F "file=@icon2.svg" \
+  -F "file=@icon3.svg" \
+  -F 'settings={"width":512,"outputFormat":"png","dpi":150}'
+```
+
+### Batch Response
+
+The batch endpoint streams a ZIP file directly with headers:
+- `Content-Type: application/zip`
+- `X-Job-Id: <jobId>`
+- `X-File-Results: <url-encoded JSON mapping of index to filename>`
+
+## Notes
+
+- Only accepts SVG and SVGZ files (validates content, not just extension). SVGZ is automatically decompressed.
+- SVG content is sanitized before rendering to prevent XSS and external resource loading.
+- The `dpi` setting controls the density at which the SVG is rasterized. Higher DPI produces larger pixel dimensions from the same SVG viewport.
+- When both `width` and `height` are provided, the image is resized using `fit: inside` (maintains aspect ratio within the bounds).
+- A `previewUrl` is included in the response for formats that browsers cannot display natively (TIFF, HEIF). The preview is a 1200px WebP thumbnail.
+- The default background `#00000000` is fully transparent. Set to `#FFFFFF` for a white background (useful with JPEG output which does not support transparency).
+- Batch processing respects the `MAX_BATCH_SIZE` server configuration and uses concurrent workers for performance.
+- Progress for batch operations can be tracked via SSE at `/api/v1/jobs/:jobId/progress`.