Record of changed resources in events is inaccurate

[squaremo]

In pkg/daemon/sync.go there's a calculation of which Kubernetes resources were changed in the most recent application, which is recorded in the event posted upstream (wherever that is). But it's pretty bogus, because

• it thinks all the resources defined in a file have changed, if that file has changed at all;
• it considers all resources generated by a .flux.yaml config to have changed, every time
• it doesn't really know what "changed" means, anyway -- any textual difference will do, whether or not it had a material affect.

I can think of a couple of ways to get a better result:

• pay attention to what kubectl reports, when applying manifests, since that gives a resource-by-resource account (though it's not always accurate itself; and parsing the output may not be a stable source of info)
• keep track of the resources from last time, and do a bytes-wise comparison to at least determine which resources really changed (if not necessarily meaningfully).

[kingdonb]

This issue is still present in Flux v2, but in a different shape.

It would mean pretty major investment in rewriting parts to fix this now, in Flux v1.

Closing, as:

• Flux v1 is in maintenance mode #3320