camel-diagram: Fix route source name stripping line numbers

[gnodet]

Fix route source display in diagram that was stripping line numbers from source names like cheese.java:9, showing just 9 instead.

Problem

extractSourceName() used lastIndexOf(':') to strip URI scheme prefixes (e.g. file:), but this also stripped line number suffixes from sources like cheese.java:9, leaving just 9.

Fix

Changed to use indexOf(':') (first colon) with a check that the part before the colon consists only of letters (a valid URI scheme like file, classpath, ref). This correctly handles:

• file:/path/to/my-route.yaml → my-route.yaml
• classpath:my-route.yaml → my-route.yaml
• cheese.java:9 → cheese.java:9 (preserved)
• file:/path/to/cheese.java:9 → cheese.java:9 (preserved)

Test plan

• Added unit tests for all source name extraction scenarios
• All 58 tests pass in camel-diagram module

[github-actions]

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[github-actions]

🧪 CI tested the following changed modules:

• components/camel-diagram

All tested modules (9 modules)

• Camel :: Diagram
• Camel :: JBang :: Console
• Camel :: JBang :: MCP
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: TUI
• Camel :: JBang :: Plugin :: Validate
• Camel :: Launcher :: Container
• Camel :: YAML DSL :: Validator
• Camel :: YAML DSL :: Validator Maven Plugin

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[davsclaus]

this is no longer needed as the json source from route structure dump has removed the line number and include this in a seperate "line" attribute

[gnodet]

Claude Code on behalf of Guillaume Nodet

True, but the code is still wrong regardless — it uses lastIndexOf(':') to strip the scheme prefix, which means it keeps only the part after the last colon rather than stripping the first part (the scheme). For example, classpath:my-route.yaml:10 would produce 10 instead of my-route.yaml:10.

The fix changes to indexOf(':') with a check that the part before the colon is all letters (a valid URI scheme), so it correctly strips only the scheme prefix.