Fixes #6674.

When dialers are missing for the current executionId, the loader currently panics and crashes the process.

This changes the behavior to:

• log an error with executionId
• attempt protocolstate.Init(typesOpts) once to initialize dialers
• if still missing: return empty slice (no panic)
• handle wait group init error gracefully

Local check:

• go test ./pkg/catalog/loader

/claim #6674

Summary by CodeRabbit

• Bug Fixes
  • Prevented crashes when required runtime connections are missing; operations now log the issue and return errors instead of terminating.
  • Avoids starting concurrent work if necessary connection resources are absent, improving startup robustness and reducing wasted processing.
  • Loading templates now fails gracefully when no templates match or initialization problems occur, providing clearer error feedback to callers.