Add WASM hidden-scan engine for the scan page

.github/workflows/ci.yml

@@ -167,3 +167,22 @@ jobs:
           name: middev-calibration-readiness
           path: calibration-readiness/
           if-no-files-found: error
+
+  wasm-scan:
+    name: WASM hidden-scan
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v7
+
+      - name: Install Rust
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: wasm32-unknown-unknown
+
+      - name: Test crate and build wasm32
+        run: |
+          cargo test --manifest-path crates/fuckmark-scan/Cargo.toml
+          cargo build --release --target wasm32-unknown-unknown --manifest-path crates/fuckmark-scan/Cargo.toml
+          test -f crates/fuckmark-scan/target/wasm32-unknown-unknown/release/fuckmark_scan.wasm
+

.gitignore

@@ -14,3 +14,4 @@ venv/
 .env.*
 .DS_Store
 artifacts/
+target/

CHANGELOG.md

@@ -15,6 +15,7 @@
 - Language-aware Trojan Source analysis and autofix. `scan_hidden_characters(..., language=)` (and lint, from the file suffix) classifies source as `comment` / `string` / code. `autofix_trojan_source` / `autofixTrojanSource` strip only `bidi_control`.
 - Zero-install hidden-Unicode scan page: `docs/scan.html` (packaged as `fuckmark/webui/scan.html`, engine copy `scan.js`). `fuckmark web` serves it at `/scan.html`. After deploy: `mark.q1z.org/scan.html`. Scanning runs in the browser; a local Python `/api/scan` confirm is optional when the CLI server is up.
 - Chromium browser extension under `editors/browser`: popup scanner, on-page reveal (badges plus CSS highlights), context-menu scan, per-tab toolbar badge, and optional paste-safe stripping that keeps real emoji ZWJ sequences (both neighbors emoji) and stops page paste handlers from seeing the raw clipboard. Zero remote code; `scan.js` matches the VS Code engine copy. Load unpacked from `chrome://extensions`.
+- WASM build of `fuckmark-hidden-scan-v1` (`crates/fuckmark-scan`, committed `fuckmark_scan.wasm`). The scan page and the Chromium popup load it when `fetch` works so classification stays on-device; `scan.js` remains the `file://` fallback. Lone UTF-16 surrogates route through the JS engine (UTF-8 cannot carry them). Empty category arrays stay empty selections. The extension CSP allows `wasm-unsafe-eval` so Chromium can instantiate the module. Page reveal and paste-safe keep the synchronous JS port. Rebuild with `crates/fuckmark-scan/build-wasm.sh`.
 - `fuckmark normalize` (`fuckmark-normalize-v1`): NFC, optional identifier lookalike fold (UTS #39-inspired subset, not a full confusable map), then strip of the security category set, plus a JSON receipt (`input_sha256` / `output_sha256` / `steps` / `report_hash`). `--clean` remains the blunt strip with no receipt. HTTP: `POST /api/normalize`. Python: `normalize_text`, `skeleton_fold`. Reference: `docs/normalize.md`.
 - VS Code / Cursor: `fuckmark.cleanOnSave` (default off) strips hidden Unicode on save.
 - Frozen confirmation files, hashes, mix mechanisms, and the published wheel are unchanged. Package version stays 0.4.1.

README.md

@@ -26,7 +26,7 @@ Opens a local page at `http://127.0.0.1:8765/mark.html`. Paste text in the brows
 `fuckmark web` also serves a local Python API. Detect and strip POST to `/api/remove-marks` and run the same engine as `fuckmark --detect`. Opening `mark.html` with `file://` or the static website has no Python process, so those paths keep the in-browser fallback.
 
 - Product paste UI source: [`docs/mark.html`](docs/mark.html) (packaged as `fuckmark/webui/mark.html`) — after deploy: [mark.q1z.org/mark.html](https://mark.q1z.org/mark.html)
-- Hidden-Unicode scan (no install): [`docs/scan.html`](docs/scan.html) — `file://` works; `fuckmark web` serves `/scan.html`; after deploy: [mark.q1z.org/scan.html](https://mark.q1z.org/scan.html)
+- Hidden-Unicode scan (no install): [`docs/scan.html`](docs/scan.html) — `file://` works; `fuckmark web` serves `/scan.html`; after deploy: [mark.q1z.org/scan.html](https://mark.q1z.org/scan.html). The page prefers a local WASM copy of the same classifier (`fuckmark_scan.wasm`) and falls back to `scan.js`.
 - Research demo: [`docs/demo.html`](docs/demo.html) — `file://` works; after deploy: [mark.q1z.org/demo.html](https://mark.q1z.org/demo.html)
 
 `mark.html` runs a local closed-set FuckMark scan, strips approved insertions when found, and on a miss shows an English no-watermark card with contact to `Fhelp@q1z.org`. Under `fuckmark web` that scan is the Python detector; the JS copy is the fallback.
@@ -181,7 +181,7 @@ The [`editors/vscode`](editors/vscode) extension reveals hidden Unicode inline a
 
 ## See it in the browser (Chrome / Edge / Brave)
 
-The [`editors/browser`](editors/browser) extension reveals hidden Unicode on the page you are reading. Load it unpacked from `chrome://extensions` (Developer mode). The popup scans pasted text or the current tab, **Reveal** paints `U+XXXX` badges on the page, and **Paste-safe** (off by default) strips hidden characters when you paste into a field while keeping emoji sequences. Nothing is uploaded; the scanner is the same `scan.js` as the editor extension. Full notes: [`editors/browser/README.md`](editors/browser/README.md).
+The [`editors/browser`](editors/browser) extension reveals hidden Unicode on the page you are reading. Load it unpacked from `chrome://extensions` (Developer mode). The popup scans pasted text or the current tab, **Reveal** paints `U+XXXX` badges on the page, and **Paste-safe** (off by default) strips hidden characters when you paste into a field while keeping emoji sequences. Nothing is uploaded. The popup prefers `fuckmark_scan.wasm` when it can fetch it; on-page reveal and paste-safe keep `scan.js`. Full notes: [`editors/browser/README.md`](editors/browser/README.md).
 
 ## Guard model input (LLM prompt-injection smuggling)
 
@@ -255,6 +255,7 @@ Frozen evidence, hashes, and protocols: [`docs/research.md`](docs/research.md).
 ```text
 python -m pip install -e ".[dev]"
 python -m pytest
+cargo test --manifest-path crates/fuckmark-scan/Cargo.toml
 ```
 
 ## License

crates/fuckmark-scan/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "fuckmark-scan"
+version = "0.4.1"
+edition = "2021"
+license = "MIT"
+publish = false
+description = "fuckmark-hidden-scan-v1 classifier for native and wasm32"
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[profile.release]
+opt-level = "z"
+lto = true
+codegen-units = 1
+panic = "abort"
+strip = true

crates/fuckmark-scan/README.md

@@ -0,0 +1,18 @@
+# fuckmark-scan (Rust / WASM)
+
+Native and `wasm32` build of `fuckmark-hidden-scan-v1`. Same category table as
+`editors/vscode/scan.js` and `fuckmark.product.scan`. No network, no extra
+crate dependencies.
+
+```text
+rustup target add wasm32-unknown-unknown
+./crates/fuckmark-scan/build-wasm.sh
+```
+
+That writes `fuckmark_scan.wasm` next to the scan page, the packaged web UI,
+and the Chromium popup. The page and popup load it when `fetch` works and keep
+`scan.js` as the `file://` fallback.
+
+`cargo test` in this directory covers classification, Trojan Source roles, and
+clean. Conformance vectors are also replayed from Python via Node on the
+committed module.

crates/fuckmark-scan/build-wasm.sh

@@ -0,0 +1,22 @@
+#!/bin/sh
+set -eu
+root="$(CDPATH= cd -- "$(dirname "$0")/../.." && pwd)"
+crate="$root/crates/fuckmark-scan"
+cd "$crate"
+rustup target add wasm32-unknown-unknown >/dev/null
+cargo test --offline --quiet 2>/dev/null || cargo test --quiet
+cargo build --release --target wasm32-unknown-unknown --quiet
+src="$crate/target/wasm32-unknown-unknown/release/fuckmark_scan.wasm"
+test -f "$src"
+for dest in \
+  "$root/editors/wasm/fuckmark_scan.wasm" \
+  "$root/docs/fuckmark_scan.wasm" \
+  "$root/fuckmark/webui/fuckmark_scan.wasm" \
+  "$root/editors/browser/fuckmark_scan.wasm"
+do
+  cp "$src" "$dest"
+done
+cp "$root/editors/wasm/scan_wasm.js" "$root/docs/scan_wasm.js"
+cp "$root/editors/wasm/scan_wasm.js" "$root/fuckmark/webui/scan_wasm.js"
+cp "$root/editors/wasm/scan_wasm.js" "$root/editors/browser/scan_wasm.js"
+wc -c "$src"