Fix RuntimeException: Unable to initialize transport handler

[ic0ns]

Summary

• Added exception handling to prevent scanner crashes when connection to target fails
• Handles both TransportHandlerConnectException and "Cannot add Tasks to already shutdown executor" errors
• Scanner now logs connection failures and continues with other probes instead of terminating

Changes

1. TlsProbe.executeState(): Added try-catch blocks to handle:

   • TransportHandlerConnectException when unable to connect to target
   • RuntimeException for "Cannot add Tasks to already shutdown executor"
   • Generic exceptions with appropriate logging

2. BleichenbacherAttacker.getServerPublicKey(): Added exception handling for connection failures during public key retrieval

3. Main.java: Added RuntimeException catch to handle scanner termination gracefully with specific handling for TransportHandlerConnectException

Test plan

• Verify code compiles successfully with mvn compile
• Ensure spotless formatting is applied
• Test scanner behavior when target becomes unreachable during scan
• Verify scanner continues with other probes after connection failure
• Check that appropriate warning/error messages are logged

Fixes #112