Add npm backfill pipeline, shared htpasswd registry auth docs

- drone npm template gains backfill-npm-from-tags (mirrors PyPI)
- document the shared /auth/htpasswd credential model (npm + PyPI +
  docker) and Verdaccio's bcrypt requirement
- point doc-weaver source/path at ../react/doc-weaver

config.yml

@@ -42,7 +42,7 @@ repos:
       mcp: { bundle: docs/mcp, server: docforge, port: 8001 }
 
   - name: doc-weaver
-    source: ../doc-weaver
+    source: ../react/doc-weaver
     title: Doc Weaver
     description: TypeScript documentation compiler using TypeDoc + JSDoc (RDFC), generating a TypeDoc site and a doc-forge-shaped MCP bundle for React packages.
     section: libraries