CAMEL-23276: Add PluginRunCustomizer to JBang Plugin SPI

[Croway]

Summary

• Adds PluginRunCustomizer interface with beforeRun(KameletMain, List<String>) hook
• Adds Plugin.getRunCustomizer() default method (follows getExporter() pattern)
• Run.run() invokes active plugin customizers after dependency resolution but before KameletMain.start()
• Respects --skip-plugins flag

This allows third-party plugins to customize the environment (system properties, config directories, initial properties) based on file arguments, without needing to subclass the Run command.

Test plan

• PluginRunCustomizerTest: verifies default returns empty, verifies customizer receives correct arguments

Claude Code on behalf of Federico Mariani

[github-actions]

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[sonarqubecloud]

Quality Gate failed

Failed conditions
0.0% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube Cloud