chore(proto): use buf managed mode for go_package instead of file options

Move go_package from individual .proto files into buf.gen.yaml managed
mode (go_package_prefix). buf injects the option at generation time only;
the proto files stay language-neutral.

https://claude.ai/code/session_01WX7GbU19M9fh3tAfAxzeET

Author: claude

proto/buf.gen.yaml

@@ -1,5 +1,11 @@
 version: v2
 clean: true
+managed:
+  enabled: true
+  override:
+    # go_package injected at generation time only; not written to .proto files.
+    - file_option: go_package_prefix
+      value: github.com/cambeerfestival/api/gen/go
 plugins:
   # OpenAPI v3 generated from the google.api.http annotations, via a BSR
   # remote plugin (no local protoc/plugin install needed).

proto/cambeerfestival/myfestival/v1alpha/bookmark.proto

@@ -3,8 +3,6 @@ syntax = "proto3";
 
 package cambeerfestival.myfestival.v1alpha;
 
-option go_package = "github.com/cambeerfestival/api/gen/go/cambeerfestival/myfestival/v1alpha;myfestivalv1alpha";
-
 import "google/api/field_behavior.proto";
 import "google/api/resource.proto";
 import "google/protobuf/timestamp.proto";

proto/cambeerfestival/myfestival/v1alpha/my_festival_service.proto

@@ -3,8 +3,6 @@ syntax = "proto3";
 
 package cambeerfestival.myfestival.v1alpha;
 
-option go_package = "github.com/cambeerfestival/api/gen/go/cambeerfestival/myfestival/v1alpha;myfestivalv1alpha";
-
 import "cambeerfestival/myfestival/v1alpha/bookmark.proto";
 import "cambeerfestival/myfestival/v1alpha/note.proto";
 import "cambeerfestival/myfestival/v1alpha/review.proto";

proto/cambeerfestival/myfestival/v1alpha/note.proto

@@ -3,8 +3,6 @@ syntax = "proto3";
 
 package cambeerfestival.myfestival.v1alpha;
 
-option go_package = "github.com/cambeerfestival/api/gen/go/cambeerfestival/myfestival/v1alpha;myfestivalv1alpha";
-
 import "google/api/field_behavior.proto";
 import "google/api/resource.proto";
 import "google/protobuf/timestamp.proto";

proto/cambeerfestival/myfestival/v1alpha/review.proto

@@ -3,8 +3,6 @@ syntax = "proto3";
 
 package cambeerfestival.myfestival.v1alpha;
 
-option go_package = "github.com/cambeerfestival/api/gen/go/cambeerfestival/myfestival/v1alpha;myfestivalv1alpha";
-
 import "google/api/field_behavior.proto";
 import "google/api/resource.proto";
 import "google/protobuf/timestamp.proto";

proto/cambeerfestival/myfestival/v1alpha/tasting.proto

@@ -3,8 +3,6 @@ syntax = "proto3";
 
 package cambeerfestival.myfestival.v1alpha;
 
-option go_package = "github.com/cambeerfestival/api/gen/go/cambeerfestival/myfestival/v1alpha;myfestivalv1alpha";
-
 import "google/api/field_behavior.proto";
 import "google/api/resource.proto";
 import "google/protobuf/timestamp.proto";