Feature/cid 2731/establish ws connection on startup

[geoandri]

🛠 Changes made

Please explain here the changes you made in this PR.

✨ Type of change

Please delete the options that are not relevant.

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

🧪 How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

• Unit tests

🏎 Checklist:

• My code follows the style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• Any dependent changes have been merged and published in downstream modules
• I have made corresponding changes to the documentation (README.md)
• My commit message clearly reflects the changes made
• Assigned the appropriate labels (version, PR type, etc.)

[github-actions]

LeanIX GitHub Agent Code Coverage

File	Coverage [61.67%]	🍏
GitHubEnterpriseProperties.kt	100%	🍏
LeanIXAuthService.kt	100%	🍏
WebSocketService.kt	100%	🍏
GradlePropertiesConfiguration.kt	82.22%	🍏
LeanIXProperties.kt	71.43%	🍏
JwtDto.kt	71.43%	🍏
GitHubAgentProperties.kt	66.67%	🍏
CachingService.kt	66.41%	🍏
WebSocketClientConfig.kt	63.71%	🍏
AgentSetupValidation.kt	56.52%	❌
GitHubAgentApplication.kt	27.27%	❌
BrokerStompSessionHandler.kt	8.43%	❌
PostStartupRunner.kt	0%	❌

Total Project Coverage	75.28%	🍏