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

public/workers/merge.worker.d.ts

@@ -1,33 +1,34 @@
 declare const coherentpdf: typeof import('../../src/types/coherentpdf.global').coherentpdf;
 
 interface MergeJob {
-    fileName: string;
-    rangeType: 'all' | 'specific' | 'single' | 'range';
-    rangeString?: string;
-    pageIndex?: number;
-    startPage?: number;
-    endPage?: number;
+  fileName: string;
+  rangeType: 'all' | 'specific' | 'single' | 'range';
+  rangeString?: string;
+  pageIndex?: number;
+  startPage?: number;
+  endPage?: number;
 }
 
 interface MergeFile {
-    name: string;
-    data: ArrayBuffer;
+  name: string;
+  data: ArrayBuffer;
 }
 
 interface MergeMessage {
-    command: 'merge';
-    files: MergeFile[];
-    jobs: MergeJob[];
+  command: 'merge';
+  files: MergeFile[];
+  jobs: MergeJob[];
+  cpdfUrl?: string;
 }
 
 interface MergeSuccessResponse {
-    status: 'success';
-    pdfBytes: ArrayBuffer;
+  status: 'success';
+  pdfBytes: ArrayBuffer;
 }
 
 interface MergeErrorResponse {
-    status: 'error';
-    message: string;
+  status: 'error';
+  message: string;
 }
 
 type MergeResponse = MergeSuccessResponse | MergeErrorResponse;