chore: update Symfony constraints to stable versions

- Remove @rc stability constraint, use stable versions
- Update to Symfony 8.0.0 stable
- Maintain backward compatibility with Symfony 3.x-8.x
- Remove minimum-stability constraint

All 327 tests pass with Symfony 8.0.0 stable.

Author: claude

composer.json

@@ -27,9 +27,9 @@
         "nikic/php-parser": "~5",
         "ondram/ci-detector": "^4.1",
         "phpstan/phpdoc-parser": "^1.2|^2.0",
-        "symfony/console": "^8.0@RC",
-        "symfony/event-dispatcher": "^8.0@RC",
-        "symfony/finder": "^8.0@RC",
+        "symfony/console": "^3.0|^4.0|^5.0|^6.0|^7.0|^8.0",
+        "symfony/event-dispatcher": "^3.0|^4.0|^5.0|^6.0|^7.0|^8.0",
+        "symfony/finder": "^3.0|^4.0|^5.0|^6.0|^7.0|^8.0",
         "symfony/polyfill-php80": "^1.20",
         "webmozart/assert": "^1.9"
     },
@@ -40,7 +40,7 @@
         "phpspec/prophecy-phpunit": "^2.3",
         "phpunit/phpunit": "^7.5|^9.0|^10.0",
         "roave/security-advisories": "dev-master",
-        "symfony/var-dumper": "^8.0@RC"
+        "symfony/var-dumper": "^3.0|^4.0|^5.0|^6.0|^7.0|^8.0"
     },
     "autoload": {
         "psr-4": {
@@ -52,8 +52,6 @@
             "Arkitect\\Tests\\": "tests/"
         }
     },
-    "minimum-stability": "RC",
-    "prefer-stable": true,
     "config": {
         "bin-dir": "bin",
         "sort-packages": true