feat(infra): add tools service with document scanner, image & PDF tools

Implement self-hosted document scanner and media processing tools as
an alternative to CamScanner/ilovepdf without third-party uploads.

Backend: Rust Axum gateway + worker pool with NATS JetStream queue
Frontend: Next.js 16 + shadcn/ui + Tailwind v4 + Framer Motion
Pipeline: Canny edge detection -> DLT homography warp -> Sauvola
binarization -> Hough deskew -> Tesseract OCR -> searchable PDF

Phase 1 (MVP) delivers:
- Document scanner with perspective correction and OCR
- Image compress/resize/convert tools
- PDF merge/split/compress tools
- Real-time WebSocket progress updates
- Rate limiting, auto-cleanup, Prometheus metrics
- Full CI/CD pipeline with Docker multi-stage build

Co-Authored-By: Kilo <kilo@kilo.ai>

apps/tools/backend/wasm/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "tools-wasm"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+wasm-bindgen = "0.2"
+image.workspace = true
+console_error_panic_hook = "0.1"
+serde.workspace = true
+serde_json.workspace = true
+
+# Skip wasm crate from default cargo check
+# Full build requires: wasm-pack build --target web