CAMEL-21960: camel-jbang - Auto-detect application.properties in run and export

[gnodet]

Summary

• Auto-detect application.properties in the base directory and include it in the files list for both camel run and camel export commands
• Previously, running camel run foo.camel.yaml would load application.properties for configuration but not include it as a file — users had to explicitly add it or use camel run *
• The profile-specific application-{profile}.properties was already auto-detected for run; this adds the same for the base application.properties, and adds both to export

Test plan

• Existing tests pass (311 tests, 0 failures)
• Manual: camel run foo.camel.yaml with application.properties in the same directory should auto-include it
• Manual: camel export with explicit files should auto-include application.properties
• Manual: camel run foo.camel.yaml application.properties should not duplicate the file
• Manual: camel run --empty should not auto-include application.properties

[github-actions]

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[github-actions]

🧪 CI tested the following changed modules:

• dsl/camel-jbang/camel-jbang-core

All tested modules (26 modules)

• Camel :: Coverage
• Camel :: Coverage [pom]
• Camel :: JBang :: Core
• Camel :: JBang :: Core [jar]
• Camel :: JBang :: Integration tests
• Camel :: JBang :: Integration tests [jar]
• Camel :: JBang :: MCP
• Camel :: JBang :: MCP [jar]
• Camel :: JBang :: Main
• Camel :: JBang :: Main [jar]
• Camel :: JBang :: Plugin :: Edit
• Camel :: JBang :: Plugin :: Edit [jar]
• Camel :: JBang :: Plugin :: Generate
• Camel :: JBang :: Plugin :: Generate [jar]
• Camel :: JBang :: Plugin :: Kubernetes
• Camel :: JBang :: Plugin :: Kubernetes [jar]
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: Route Parser [jar]
• Camel :: JBang :: Plugin :: Testing
• Camel :: JBang :: Plugin :: Testing [jar]
• Camel :: JBang :: Plugin :: Validate
• Camel :: JBang :: Plugin :: Validate [jar]
• Camel :: Launcher
• Camel :: Launcher [jar]
• Camel :: Launcher :: Container
• Camel :: Launcher :: Container [pom]