The Convert Audio tool promised configurable bitrate, sample rate, and channel count, but only format and bitrate were exposed. Adds an optional sampleRate setting (8000 to 96000 Hz, omitted = preserve source) wired through the Zod schema, the FFmpeg -ar flag, the standalone settings panel, and the pipeline builder controls.
Impossible combinations fail loudly instead of degrading silently: MP3 + 96000 Hz is rejected (libmp3lame caps at 48 kHz), and MP3 bitrates above the encoder ceiling at low rates (64 kbps at 8 kHz, 160 kbps at 16/22.05 kHz) are rejected rather than clamped. The UI offers only legal combinations and sanitizes stored pipeline settings on load.
Docs updated in English plus all 20 localized pages with refreshed i18n_source_hash stamps; two new UI strings added to all 21 locales.
Fixes#558
Shared Claude Code translation pipeline (scripts/i18n, no API key) plus Astro/VitePress/Scalar i18n wiring. Landing and API reference translated into all 20 languages; docs i18n wiring + English source anchors. The translated docs markdown (apps/docs/<locale>/**, 3,620 files) follows in a companion PR because it exceeds GitHub's per-PR CI file limit.
Reconcile every tool page's parameters, defaults, and response shape against the tool's Zod settings schema and executionHint in code. Notable fixes: color-palette (add count + format params, hex output, median-cut algorithm), favicon (add 5 params, was documented as having none), qr-generate (add logoDataUri), convert (add ppm/eps/tga formats), video-loudnorm (-16 LUFS not -14), smart-crop (async 202 not sync 200), images-to-video (1080x1080 square), and several output-filename and behavior-note corrections.
Also normalize API endpoint paths to /api/v1/tools/<id> (no modality segment) and standardize curl examples on the Docker API port 1349. Verified with a clean docs build.
Move all 157 tool pages into image/video/audio/pdf/data subfolders so URLs read /tools/<modality>/<id> (e.g. /tools/image/crop). Nest the image sub-categories under an Image group in the sidebar so the nav reads by modality. Add public/_redirects (301, clean + .html forms) mapping every old flat /tools/<id> URL to its new path so inbound links keep working. Rewrite all internal /tools links. Verified with a clean docs build (no dead links).
