refactor: enforce P1.1 registry path ownership

backend/src/workspaces/schema.ts

@@ -341,7 +341,7 @@ function workspaceInvariants(workspace: any, context: z.RefinementCtx): void {
   unique(workspace.llm_policy.allowed, context, ["llm_policy", "allowed"]);
 
   if (workspace.evidence?.source.type === "filesystem") {
-    const expected = `workspace-content/${workspace.workspace.id}/evidence`;
+    const expected = `${workspace.workspace.id}/evidence`;
     if (workspace.evidence.source.uri !== expected) {
       context.addIssue({
         code: "custom",