Rename Go module paths to repo.anhonesthost.net/CyberCoveLLC/threshold

Rename root, api and sdk module paths (imports, go.mod, go_package,
ldflags, build scripts, buf configs) and regenerate protobuf/gateway
code with the project's pinned toolchain. Wire identifiers unchanged.
api gets a local replace for sdk; root/api/sdk require v0.1.0.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

internal/proto/controller/api/resources/billing/v1/billing.proto

@@ -7,7 +7,7 @@ package controller.api.resources.billing.v1;
 
 import "google/protobuf/timestamp.proto";
 
-option go_package = "github.com/hashicorp/boundary/sdk/pbs/controller/api/resources/billing;billing";
+option go_package = "repo.anhonesthost.net/CyberCoveLLC/threshold/sdk/pbs/controller/api/resources/billing;billing";
 
 message ActiveUsers {
   // Output only. The number of active users between the start time and end time.