Implement authentication

[anmazzotti]

Closes rancher/elemental#989

[codecov]

Codecov Report

Merging #8 (ca835d6) into main (9952df2) will increase coverage by 0.20%.
The diff coverage is 51.59%.

@@            Coverage Diff             @@
##             main       #8      +/-   ##
==========================================
+ Coverage   48.36%   48.57%   +0.20%     
==========================================
  Files          36       38       +2     
  Lines        2634     3014     +380     
==========================================
+ Hits         1274     1464     +190     
- Misses       1176     1322     +146     
- Partials      184      228      +44     

Files	Coverage Δ
api/v1beta1/elementalhost_types.go	100.00% <ø> (ø)
api/v1beta1/elementalregistration_types.go	100.00% <ø> (ø)
api/v1beta1/zz_generated.deepcopy.go	24.45% <100.00%> (+0.75%)	⬆️
internal/api/types.go	79.31% <100.00%> (+1.12%)	⬆️
internal/api/elementalregistration_controller.go	49.18% <10.00%> (-7.69%)	⬇️
cmd/agent/main.go	74.61% <61.53%> (-1.17%)	⬇️
internal/identity/manager.go	58.62% <58.62%> (ø)
internal/identity/ed25519.go	60.00% <60.00%> (ø)
internal/agent/client/client.go	58.46% <66.66%> (+1.97%)	⬆️
...nal/controller/elementalregistration_controller.go	68.99% <68.23%> (+5.35%)	⬆️
... and 2 more

... and 1 file with indirect coverage changes