feat: add custom domain support for GitHub Pages

Adds src/CNAME (javaamazonas.com.br) and includes it in the Angular
build assets so it is copied into dist/java-amazonas/browser and
published by the Actions-based Pages deploy workflow.

Do not merge until DNS at the registrar is confirmed propagated
(nslookup javaamazonas.com.br resolving to GitHub Pages' IPs) —
merging activates GitHub Pages' automatic redirect from
javaamazonas.github.io to the custom domain, which takes the site
down if DNS isn't ready yet (this happened once already).

Author: samuelsonbrito

angular.json

@@ -18,7 +18,7 @@
             "browser": "src/main.ts",
             "polyfills": ["zone.js"],
             "tsConfig": "tsconfig.app.json",
-            "assets": ["src/favicon.ico", "src/assets"],
+            "assets": ["src/favicon.ico", "src/CNAME", "src/assets"],
             "styles": [
               "src/styles.css"
             ],

src/CNAME

@@ -0,0 +1 @@
+javaamazonas.com.br