Rust: small fixes to protobuf_well_known_types crate

Use the `substitute_rust_release_version()` macro instead of a one-off genrule.
Also update lib.rs to reflect that we now generate a `generated.rs` file that
exports code for all the .proto files, instead of having a primary `pb.rs`
file.

PiperOrigin-RevId: 730882117

rust/release_crates/protobuf_well_known_types/BUILD.bazel

@@ -1,6 +1,6 @@
 load("@rules_pkg//pkg:mappings.bzl", "pkg_files", "strip_prefix")
 load("@rules_pkg//pkg:tar.bzl", "pkg_tar")
-load("//:protobuf_version.bzl", "PROTOBUF_RUST_VERSION")
+load("//rust/release_crates:substitute_rust_release_version.bzl", "substitute_rust_release_version")
 
 pkg_tar(
     name = "crate",
@@ -18,16 +18,14 @@ pkg_files(
     strip_prefix = strip_prefix.from_root("rust/release_crates/protobuf_well_known_types"),
 )
 
-genrule(
-    name = "gen_cargo_toml",
-    srcs = ["Cargo-template.toml"],
-    outs = ["Cargo.toml"],
-    cmd = "cat $(SRCS) | sed -e 's/{{VERSION}}/{0}-beta/g' > $(OUTS)".format(PROTOBUF_RUST_VERSION),
+substitute_rust_release_version(
+    src = "Cargo-template.toml",
+    out = "Cargo.toml",
 )
 
 filegroup(
     name = "srcs",
-    srcs = [":gen_cargo_toml"] + glob(["**/*"]),
+    srcs = ["Cargo.toml"] + glob(["**/*"]),
     visibility = ["//rust:__subpackages__"],
 )
 

rust/release_crates/protobuf_well_known_types/src/lib.rs

@@ -1 +1 @@
-include!(concat!(env!("OUT_DIR"), "/protobuf_generated/google/protobuf/any.u.pb.rs"));
+include!(concat!(env!("OUT_DIR"), "/protobuf_generated/google/protobuf/generated.rs"));