fix: add upper bound to Angular version ranges

- Change peerDependencies from >=18.0.0 to >=18.0.0 <22.0.0
- Explicitly support Angular 18, 19, 20, 21
- Update docs to reflect v3.x as current version

Author: JohannesHoppe

README.md

@@ -97,7 +97,7 @@ If this is not the folder that you want to serve, you should explicitly specify
 ng deploy --dir=dist/test/browser
 ```
 
-This new build logic is a breaking change, therefore `angular-cli-ghpages` v2 requires Angular 18 or higher.
+This new build logic is a breaking change, therefore `angular-cli-ghpages` v2+ requires Angular 18 or higher.
 For previous versions of Angular, use `angular-cli-ghpages` v1.x.
 
 ## ⚠️ Prerequisites <a name="prerequisites"></a>

docs/README_contributors.md

@@ -35,8 +35,9 @@ Follow the instructions for [checking and updating the Angular CLI version](#ang
 This builder requires the method `getTargetOptions()` from the Angular DevKit which was introduced [here](https://github.com/angular/angular-cli/pull/13825/files).
 
 **Version compatibility:**
-- **v2.x:** Supports Angular 18 and higher (current version)
-- **v1.x:** Supported Angular 9-17 (now deprecated for new projects)
+- **v3.x:** Supports Angular 18 and higher (current version)
+- **v2.x:** Supported Angular 18 (previous major version)
+- **v1.x:** Supported Angular 9-17 (deprecated)
 
 Execute the next three steps to update your test project to the latest Angular version.
 

src/package.json

@@ -72,13 +72,13 @@
     "typescript": "~5.2.2"
   },
   "dependencies": {
-    "@angular-devkit/architect": ">=0.1800.0",
-    "@angular-devkit/core": ">=18.0.0",
-    "@angular-devkit/schematics": ">=18.0.0",
+    "@angular-devkit/architect": ">=0.1800.0 <0.2200.0",
+    "@angular-devkit/core": ">=18.0.0 <22.0.0",
+    "@angular-devkit/schematics": ">=18.0.0 <22.0.0",
     "fs-extra": "^11.2.0",
     "gh-pages": "6.3.0"
   },
   "peerDependencies": {
-    "@angular/cli": ">=18.0.0"
+    "@angular/cli": ">=18.0.0 <22.0.0"
   }
 }