Remove `copts` for `cc_library` targets using `nanopb` protos

[Andrewyx]

Description of the task

As a result of the Bazel 8 migration, a problem was noticed which forced the usage of copts = ["-Iexternal/nanopb+"]. This was the result of changes to nanopb and protobuf libraries (and also the protoc compilerandnanopb.bzl(our nanopb library rule) which failed to linknanopb` deps to nanopb generated headers and c implementations.

We should modify nanopb.bzl so that copts = ["-Iexternal/nanopb+"] is not necessary in every target.

Acceptance criteria

• Removal of copts = ["-Iexternal/nanopb+"] from all parts of the current code base

Blocked By

• Andrewyx/Upgrade Bazel 8 #3459

[Lmh-java]

Might be addressed by #3459 as well.