fine grained dependency beween the api proto

*Title*: *fine grained dependency beween the api proto*

Now in our proto API, every bazel package only contains one build target. That means all these dependencis are using the package as the basic unit.

That make it's easy to result in cycle dependency and we have encountered related problem. For example, the TypedExtensionConfig in the StringMatcher. When we want to TypedExtensionConfig to the StringMatcher, because the `envoy/config/core/v3` have depended the `envoy/type/matcher/v3`, we cannot use config.core.v3.TypedExtensionConfig in the matcher package and finally the TypedExtensionConfig in the cncf/xds is used. (Of course, specific to the TypedExtensionConfig, cncf/xds may be an acceptable option, but this example is enough to elucidate the problem.)