all: scrub stale gRPC references from comments and docs

Reword comments and docs that still named the removed gRPC stack, rename
the GRPCSortable test interface, and drop the dead gRPC port note from the
dev README.

hscontrol/api/v1/apikeys.go

@@ -77,7 +77,7 @@ func (s *Server) DeleteApiKey(_ context.Context, params oas.DeleteApiKeyParams)
 }
 
 // apiKeyByIDOrPrefix looks up an API key by exactly one of id or prefix.
-// Providing neither or both is a 400, matching the gRPC contract.
+// Providing neither or both is a 400.
 func (s *Server) apiKeyByIDOrPrefix(
 	id uint64,
 	prefix string,

hscontrol/api/v1/convert.go

@@ -11,12 +11,11 @@ import (
 
 // This file converts the state-layer types into the ogen API types. It reads
 // the copy-on-write view types (NodeView, UserView, PreAuthKeyView) directly so
-// no node/user is deep-copied on the read path, and reproduces exactly what the
-// previous proto builders emitted — username fallback, masked key prefixes,
-// online computation, the register-method enum.
+// no node/user is deep-copied on the read path, and reproduces the same fields
+// the previous API emitted — username fallback, masked key prefixes, online
+// computation, the register-method enum.
 //
-// Unlike grpc-gateway (which marshalled with EmitUnpopulated), these converters
-// omit zero-value and absent fields — empty strings, false booleans, zero
+// These converters omit zero-value and absent fields — empty strings, false booleans, zero
 // numbers, empty arrays, nil timestamps/objects, and the unspecified register
 // method. See docs/v1-ogen/CHANGES.md.
 

hscontrol/api/v1/health.go

@@ -7,7 +7,7 @@ import (
 )
 
 // Health reports server health, including database connectivity. A failed
-// database ping is a 500; the gRPC implementation likewise returned the ping
+// database ping is a 500; the previous implementation likewise returned the ping
 // error (the body's databaseConnectivity flag was never observable on failure).
 func (s *Server) Health(ctx context.Context) (*oas.HealthOK, error) {
 	err := s.state.PingDB(ctx)

hscontrol/api/v1/server.go

@@ -19,9 +19,8 @@ import (
 
 // Server implements the generated [oas.Handler] and [oas.SecurityHandler].
 //
-// Operations that have not been migrated from the gRPC stack yet are inherited
-// from [oas.UnimplementedHandler] and return 501; each resource group replaces
-// its stubs as it is converted.
+// Any operation not implemented here is inherited from
+// [oas.UnimplementedHandler] and returns 501; every operation is implemented.
 type Server struct {
 	oas.UnimplementedHandler