Say LibrePortal is licensed under AGPL-3.0-or-later

The licence text is unchanged. The README, the Promise and the contributing
guide now name it exactly (version 3, or any later version), the README
carries the SPDX identifier, and the WebUI backend's package.json declares it.

Assisted-by: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -19,7 +19,7 @@ toggle — it's the whole point.
 
 ## Free & open — forever
 
-The entire platform is **free software under the [GNU AGPLv3](LICENSE)**.
+The entire platform is **free software under the [GNU AGPL-3.0-or-later](LICENSE)**.
 Self-host it and you get **everything** — every feature, no paywalls, no
 telemetry. See [our Promise](docs/guide/promise.md) for exactly what that means.
 
@@ -76,4 +76,7 @@ into the platform it is today.
 
 ## License
 
-[GNU AGPLv3](LICENSE). What's open stays open.
+[GNU AGPL-3.0-or-later](LICENSE): version 3 of the GNU Affero General Public
+License, or (at your option) any later version. What's open stays open.
+
+SPDX-License-Identifier: AGPL-3.0-or-later

containers/libreportal/backend/package-lock.json

@@ -7,6 +7,7 @@
     "": {
       "name": "libreportal-web-backend",
       "version": "1.0.0",
+      "license": "AGPL-3.0-or-later",
       "dependencies": {
         "bcryptjs": "^2.4.3",
         "compression": "^1.8.1",

containers/libreportal/backend/package.json

@@ -1,6 +1,7 @@
 {
   "name": "libreportal-web-backend",
   "version": "1.0.0",
+  "license": "AGPL-3.0-or-later",
   "main": "server.js",
   "dependencies": {
     "bcryptjs": "^2.4.3",

docs/contributing/contributing.md

@@ -5,7 +5,7 @@ contributions are genuinely welcome.
 
 ## Ground rules
 
-- LibrePortal is **AGPLv3**. By contributing, your work is offered under that
+- LibrePortal is **AGPL-3.0-or-later**. By contributing, your work is offered under that
   same license (see the DCO below).
 - **Match the surrounding code** — keep it simple and readable, and follow
   the style of the file you're editing.
@@ -30,7 +30,7 @@ Signed-off-by: Your Name <you@example.com>
 
 By signing off, you agree to the DCO: that you wrote the patch (or otherwise
 have the right to submit it) and that it may be included under the project's
-AGPLv3 license.
+AGPL-3.0-or-later license.
 
 ## Bugs & ideas
 

docs/guide/promise.md

@@ -7,7 +7,7 @@ to you — in plain language, so you can hold us to it.
 
 You can **run, study, modify, share, and fully use 100% of LibrePortal —
 every feature — for free, forever.** The entire platform is licensed under
-the GNU AGPLv3 (see [LICENSE](../../LICENSE)). There are **no feature paywalls in
+the GNU AGPL-3.0-or-later (see [LICENSE](../../LICENSE)). There are **no feature paywalls in
 the software, no crippled "community edition," and no telemetry** phoning
 home.