Improve early validation of Kubernetes manifests

[ilya-lesikov]

Before proceeding

• I didn't find a similar issue

Problem

Currently we do not properly validate Kubernetes manifests before deploying them. There is dry-run Apply happening in Plan construction, but we ignore its errors due to many false-positives.

Solution (if you have one)

We can validate resources early based on:

• builtin schemas from Kubernetes library
• schemas grabbed from Kubernetes API
• schemas produced from CRDs in charts (might be difficult to do)

Additional information

No response