feat: separate AGPL libraries and add dynamic WASM loading

- Add WASM settings page for configuring external AGPL modules
- Implement dynamic loading for PyMuPDF, Ghostscript, and CoherentPDF
- Add Cloudflare Worker proxy for serving WASM files with CORS
- Update all affected tool pages to check WASM availability
- Add showWasmRequiredDialog for missing module configuration

Documentation:
- Update README, licensing.html, and docs to clarify AGPL components
  are not bundled and must be configured separately
- Add WASM-PROXY.md deployment guide with recommended source URLs
- Rename "CPDF" to "CoherentPDF" for consistency

src/js/utils/ghostscript-dynamic-loader.ts

@@ -0,0 +1,89 @@
+import { WasmProvider } from './wasm-provider.js';
+
+let cachedGS: any = null;
+let loadPromise: Promise<any> | null = null;
+
+export interface GhostscriptInterface {
+  convertToPDFA(pdfBuffer: ArrayBuffer, profile: string): Promise<ArrayBuffer>;
+  fontToOutline(pdfBuffer: ArrayBuffer): Promise<ArrayBuffer>;
+}
+
+export async function loadGhostscript(): Promise<GhostscriptInterface> {
+  if (cachedGS) {
+    return cachedGS;
+  }
+
+  if (loadPromise) {
+    return loadPromise;
+  }
+
+  loadPromise = (async () => {
+    const baseUrl = WasmProvider.getUrl('ghostscript');
+    if (!baseUrl) {
+      throw new Error(
+        'Ghostscript is not configured. Please configure it in Advanced Settings.'
+      );
+    }
+
+    const normalizedUrl = baseUrl.endsWith('/') ? baseUrl : `${baseUrl}/`;
+
+    try {
+      const wrapperUrl = `${normalizedUrl}gs.js`;
+
+      await loadScript(wrapperUrl);
+
+      const globalScope =
+        typeof globalThis !== 'undefined' ? globalThis : window;
+
+      if (typeof (globalScope as any).loadGS === 'function') {
+        cachedGS = await (globalScope as any).loadGS({
+          baseUrl: normalizedUrl,
+        });
+      } else if (typeof (globalScope as any).GhostscriptWASM === 'function') {
+        cachedGS = new (globalScope as any).GhostscriptWASM(normalizedUrl);
+        await cachedGS.init?.();
+      } else {
+        throw new Error(
+          'Ghostscript wrapper did not expose expected interface. Expected loadGS() or GhostscriptWASM class.'
+        );
+      }
+
+      return cachedGS;
+    } catch (error: any) {
+      loadPromise = null;
+      throw new Error(
+        `Failed to load Ghostscript from ${normalizedUrl}: ${error.message}`
+      );
+    }
+  })();
+
+  return loadPromise;
+}
+
+function loadScript(url: string): Promise<void> {
+  return new Promise((resolve, reject) => {
+    if (document.querySelector(`script[src="${url}"]`)) {
+      resolve();
+      return;
+    }
+
+    const script = document.createElement('script');
+    script.src = url;
+    script.type = 'text/javascript';
+    script.async = true;
+
+    script.onload = () => resolve();
+    script.onerror = () => reject(new Error(`Failed to load script: ${url}`));
+
+    document.head.appendChild(script);
+  });
+}
+
+export function isGhostscriptAvailable(): boolean {
+  return WasmProvider.isConfigured('ghostscript');
+}
+
+export function clearGhostscriptCache(): void {
+  cachedGS = null;
+  loadPromise = null;
+}