Update repository URLs to Gitea

- Change all URLs from github.com to opensource.rogarithm.net
- Update Docker image references to local build (php-security-linter:latest)
- Fix Gitea Issues URL in CONTRIBUTING.md

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CONTRIBUTING.md

@@ -10,7 +10,7 @@ Please be respectful and constructive in all interactions. We welcome contributo
 
 ### Reporting Bugs
 
-1. Check if the issue already exists in [GitHub Issues](https://github.com/security-linter/php-laravel/issues)
+1. Check if the issue already exists in [Gitea Issues](https://opensource.rogarithm.net/rogarithm/php-security-linter/issues)
 2. If not, create a new issue with:
    - Clear description of the problem
    - Steps to reproduce
@@ -52,7 +52,7 @@ Security linters can produce false positives (safe code flagged as vulnerable) o
 ### Installation
 
 ```bash
-git clone https://github.com/security-linter/php-laravel.git
+git clone https://opensource.rogarithm.net/rogarithm/php-security-linter.git
 cd php-laravel
 composer install
 ```