feat(sidekick/rust): change README for GA clients (#1889)

Author: coryan

internal/sidekick/internal/rust/annotate.go

@@ -74,6 +74,12 @@ func (m *modelAnnotations) IsGaxiCrate() bool {
 	return m.PackageName == "google-cloud-gax-internal"
 }
 
+// ReleaseLevelIsGA returns true if the ReleaseLevel attribute indicates this
+// is a GA library.
+func (m *modelAnnotations) ReleaseLevelIsGA() bool {
+	return m.ReleaseLevel == "GA"
+}
+
 type serviceAnnotations struct {
 	// The name of the service. The Rust naming conventions requires this to be
 	// in `PascalCase`. Notably, names like `IAM` *must* become `Iam`, but

internal/sidekick/internal/rust/templates/common/README.md.mustache

@@ -17,13 +17,15 @@ limitations under the License.
 
 <!-- Code generated by sidekick. DO NOT EDIT. -->
 
+{{^Codec.ReleaseLevelIsGA}}
 **FEEDBACK WANTED:** We believe the APIs in this crate are stable, and
 do not anticipate any breaking changes are needed. We are looking for
 feedback before labeling the APIs "1.0". Changes (even breaking changes)
 are still possible, but not expected.
 
 We also believe the implementation is ready for production, bugs are
 still possible, but not expected.
+{{/Codec.ReleaseLevelIsGA}}
 {{#Codec.Incomplete}}
 
 **WARNING:** some RPCs have no corresponding Rust function to call them.
@@ -37,6 +39,14 @@ GitHub repository.
 
 {{{.}}}
 {{/Description}}
+{{#Codec.ReleaseLevelIsGA}}
+
+The client library types and functions are stable and not expected to change.
+Please note that Google Cloud services do change from time to time. The client
+libraries are designed to preserve backwards compatibility when the service
+changes in compatible ways. For example, adding RPCs, or fields to messages
+should not introduce breaking changes to the client libraries.
+{{/Codec.ReleaseLevelIsGA}}
 {{#Codec.HasServices}}
 
 ## Quickstart

internal/sidekick/internal/rust/templates/crate/src/lib.rs.mustache

@@ -19,6 +19,7 @@ limitations under the License.
 {{/Codec.BoilerPlate}}
 
 //! Google Cloud Client Libraries for Rust - {{{Title}}}
+//! {{^Codec.ReleaseLevelIsGA}}
 //!
 //! **FEEDBACK WANTED:** We believe the APIs in this crate are stable, and
 //! do not anticipate any breaking changes are needed. We are looking for
@@ -27,6 +28,7 @@ limitations under the License.
 //!
 //! We also believe the implementation is ready for production, bugs are
 //! still possible, but not expected.
+//! {{/Codec.ReleaseLevelIsGA}}
 //! {{#Codec.Incomplete}}
 //!
 //! **WARNING:** some RPCs have no corresponding Rust function to call them.
@@ -39,7 +41,16 @@ limitations under the License.
 //!
 //! This crate contains traits, types, and functions to interact with {{{Title}}}
 //! Most applications will use the structs defined in the [client] module.
-//! More specifically:
+//! {{#Codec.ReleaseLevelIsGA}}
+//! 
+//! The client library types and functions are stable and not expected to change.
+//! Please note that Google Cloud services do change from time to time. The client
+//! libraries are designed to preserve backwards compatibility when the service
+//! changes in compatible ways. For example, adding RPCs, or fields to messages
+//! should not introduce breaking changes to the client libraries.
+//! {{/Codec.ReleaseLevelIsGA}}
+//!
+//! # Available Clients
 //!
 {{#Codec.Services}}
 //! * [{{Codec.Name}}](client/struct.{{Codec.Name}}.html)