fix(security): harden sanitize, flatten, redaction, signature validation, CSP, proxies and CI

serve.json

@@ -3,6 +3,10 @@
     {
       "source": "**/*",
       "headers": [
+        {
+          "key": "Content-Security-Policy",
+          "value": "default-src 'self'; script-src 'self' 'wasm-unsafe-eval' 'unsafe-eval' blob: https://cdn.jsdelivr.net/npm/@bentopdf/pymupdf-wasm@0.11.16/ https://cdn.jsdelivr.net/npm/@bentopdf/gs-wasm@0.1.1/assets/ https://cdn.jsdelivr.net/npm/coherentpdf@2.5.5/dist/ https://cdn.jsdelivr.net/npm/tesseract.js@v7.0.0/dist/ https://cdn.jsdelivr.net/npm/tesseract.js-core@v7.0.0/; worker-src 'self' blob:; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com; img-src 'self' data: blob: https:; font-src 'self' data: https://fonts.gstatic.com https://rawcdn.githack.com; connect-src 'self' blob: https://api.github.com https://fonts.gstatic.com https://cdn.jsdelivr.net https://bentopdf-cors-proxy.bentopdf.workers.dev https://rawcdn.githack.com; object-src 'none'; base-uri 'self'; frame-src 'self' blob:; frame-ancestors 'self'; form-action 'self'"
+        },
         {
           "key": "Cross-Origin-Opener-Policy",
           "value": "same-origin"
@@ -20,6 +24,15 @@
           "value": "nosniff"
         }
       ]
+    },
+    {
+      "source": "docs/**",
+      "headers": [
+        {
+          "key": "Content-Security-Policy",
+          "value": "default-src 'self'; script-src 'self' 'sha256-DQUgNM9X0iH2019NkUxeBvnBoEoRKkHBc/I0iLqPNPA=' 'sha256-La1r0VSk0Po4KFI0duEKhmPu+u0I416JW3oONqtdf4M='; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com; img-src 'self' data: blob: https:; font-src 'self' data: https://fonts.gstatic.com https://rawcdn.githack.com; connect-src 'self' https://api.github.com https://fonts.gstatic.com https://cdn.jsdelivr.net https://bentopdf-cors-proxy.bentopdf.workers.dev https://rawcdn.githack.com; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; form-action 'self'"
+        }
+      ]
     }
   ],
   "cleanUrls": true,