Support resourceMatchers in searchRules

**Describe the problem/challenge you have**

The existing [key matcher](https://carvel.dev/kbld/docs/latest/config/#key-matcher) and [value matcher](https://carvel.dev/kbld/docs/latest/config/#value-matcher) are quite limited.

For example, let's say I have a `ConfigMap` with an `image` field:
```yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: image-config
data:
image: foo
```

You could use a key matcher to `name: image` and `path: [data]`, but that would potentially catch other resources (ConfigMaps or otherwise) that you didn't mean to include.

Alternatively, you could use a value matcher, but that can also suffer from false positives and requires knowing the image name and/or repo ahead of time.

**Describe the solution you'd like**

Support resourceMatchers, similar to what kapp does: https://carvel.dev/kapp/docs/latest/config/#resource-matchers. This would allow targeting specific kinds (ConfigMap) and names.

Once the resource matcher filters down to the resource(s), I think you'd still need the ability to specify paths *inside* the resource though.

**Anything else you would like to add:**
https://kubernetes.slack.com/archives/CH8KCCKA5/p1635201137105000?thread_ts=1635197514.098700&cid=CH8KCCKA5

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Start by tracing the searchRules configuration and the existing key matcher and value matcher behavior, then compare the requested resourceMatchers semantics with kapp's resource-matchers documentation. Done should include targeting resources by kind and name while still allowing paths inside the selected resource, with coverage for the ConfigMap image example.

Written by the indexing model from the issue text.