fix: Empty camel routes should show basic skeleton

[Delawen]

Fixes KaotoIO/kaoto-ui#2056

Something like

- route:
    id: empty-route
    from:
      uri: null
      steps: []

Should return the same when pass through the API.

[Delawen]

Fixes KaotoIO/kaoto-ui#2090 too

[codecov]

Codecov Report

Merging #759 (cd093e5) into main (607a486) will increase coverage by 0.30%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##               main     #759      +/-   ##
============================================
+ Coverage     78.61%   78.92%   +0.30%     
  Complexity      160      160              
============================================
  Files            54       54              
  Lines          2965     2980      +15     
  Branches        502      506       +4     
============================================
+ Hits           2331     2352      +21     
+ Misses          424      417       -7     
- Partials        210      211       +1     

see 4 files with indirect coverage changes

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
1 Code Smell

No Coverage information
2.6% Duplication