CAMEL-23226: Add init --list and export --dry-run to camel-jbang

[gnodet]

JIRA: CAMEL-23226

Summary

• Add --list option to the camel init command to discover available templates grouped by category (Routes, Kamelets, Pipes/CRs, REST). Internal templates (POM, Dockerfile) are excluded from listing.
• Add --dry-run option to camel export that shows what would be generated (runtime, GAV, dependencies, build tool) without creating files
• Add InitTest unit tests for the --list functionality

Test plan

• Run camel init --list and verify templates are grouped by category
• Run camel export --dry-run and verify output shows planned export details without creating files
• Run InitTest unit tests

[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]