Add PHP Analyzer Plugin and Composer Lock Data Handling

- Implemented the PhpAnalyzerPlugin to analyze PHP projects.
- Created ComposerLockData class to represent data from composer.lock files.
- Developed ComposerLockReader to load and parse composer.lock files asynchronously.
- Introduced ComposerPackage class to encapsulate package details.
- Added PhpPackage class to represent PHP packages with metadata and evidence.
- Implemented PhpPackageCollector to gather packages from ComposerLockData.
- Created PhpLanguageAnalyzer to perform analysis and emit results.
- Added capability signals for known PHP frameworks and CMS.
- Developed unit tests for the PHP language analyzer and its components.
- Included sample composer.lock and expected output for testing.
- Updated project files for the new PHP analyzer library and tests.

src/Scanner/__Libraries/StellaOps.Scanner.Analyzers.Lang.Php/PhpAnalyzerPlugin.cs

@@ -0,0 +1,16 @@
+using StellaOps.Scanner.Analyzers.Lang.Plugin;
+
+namespace StellaOps.Scanner.Analyzers.Lang.Php;
+
+public sealed class PhpAnalyzerPlugin : ILanguageAnalyzerPlugin
+{
+    public string Name => "StellaOps.Scanner.Analyzers.Lang.Php";
+
+    public bool IsAvailable(IServiceProvider services) => services is not null;
+
+    public ILanguageAnalyzer CreateAnalyzer(IServiceProvider services)
+    {
+        ArgumentNullException.ThrowIfNull(services);
+        return new PhpLanguageAnalyzer();
+    }
+}