feat: integrate PDF Tools with toolbox portal

README.md

@@ -120,6 +120,17 @@ browser  <-- HTTPS -->  static web server / reverse proxy  -->  built app assets
 
 There is no application server to operate. Administrators only need to host the built files from `dist/`.
 
+The production build is relocatable and can also be assembled into an
+[Add Ideas Toolbox](https://git.add-ideas.de/zemion/toolbox-portal) deployment.
+`toolbox-app.json` describes this app through the framework-independent
+[Toolbox App Contract](https://git.add-ideas.de/zemion/toolbox-sdk). The same
+artifact remains fully usable on its own.
+
+When launched with a same-origin catalogue URL, for example
+`?toolbox=/toolbox.catalog.json`, the shared first-party shell adds a toolbox
+home link and application switcher. Missing, invalid, and cross-origin
+catalogues are ignored so the app falls back to standalone mode.
+
 ### Build and test from source
 
 ```bash
@@ -138,6 +149,19 @@ npm run build
 
 The production build is written to `dist/`.
 
+Create a versioned, checksummed release artifact with:
+
+```bash
+npm run release:artifact
+```
+
+This writes `release/pdf-tools-<version>.zip` and its `.sha256` file. The ZIP
+contains the static app, its toolbox manifest and changelog, plus the application
+source-code location, license, and the full license/notice texts found for
+bundled runtime dependencies under `LICENSES/`. Existing artifacts for the same
+version are never replaced implicitly; after intentionally reviewing a rebuild, use
+`npm run release:artifact -- --force`.
+
 Useful individual development commands:
 
 ```bash
@@ -272,4 +296,4 @@ The roadmap and non-goals now live in [`ROADMAP.md`](ROADMAP.md). Open roadmap i
 
 ## License
 
-GPL-3.0. See `LICENSE`.
+AGPL-3.0-only. See `LICENSE`.