fix: use sha256 descriptor digest and keep operator errors fully sanitized

backend/src/workspace-maintenance.ts

@@ -41,10 +41,9 @@ function boundedJson(result: WorkspaceOperationResult): string {
   return encoded;
 }
 
-function sanitizeStderr(error: unknown): string {
-  const detail = error instanceof Error ? error.message : String(error);
-  const safe = detail.replace(/[\r\n]+/g, " ").slice(0, 512);
-  return safe.length > 0 ? `workspace maintenance failed: ${safe}\n` : "workspace maintenance failed\n";
+function sanitizeStderr(_error: unknown): string {
+  // Never return raw exception text: it may embed endpoints, tokens, or SQL.
+  return "workspace maintenance failed\n";
 }
 
 function parseRequest(command: string, stdin: string): Record<string, unknown> {

backend/src/workspaces/preprocessing-service.ts

@@ -129,8 +129,7 @@ export class WorkspacePreprocessingService {
           { kind: "runtime_config", digest: runtime.configLease.configDigest },
         ],
       });
-    } catch (error) {
-      const detail = error instanceof Error ? error.message : String(error);
+    } catch {
       return {
         schemaVersion: 1,
         status: "failed",
@@ -140,7 +139,6 @@ export class WorkspacePreprocessingService {
         descriptorBlob: "",
         operation: "inspect",
         completedStages: [],
-        warnings: detail.length > 0 ? [detail.slice(0, 512)] : undefined,
       };
     }
   }

backend/src/workspaces/runtime-config-lease.ts

@@ -352,7 +352,8 @@ export async function renderActiveWorkspaceRuntime(options: {
   const repository = new GitWorkspaceRepository(options.registryConfig);
   await repository.ensureLayout();
   const snapshotPath = options.registry.snapshotPath(revision.commit, revision.id);
-  const workspace = parseWorkspaceYaml(await readFileAsync(snapshotPath, "utf8"));
+  const descriptorSource = await readFileAsync(snapshotPath, "utf8");
+  const workspace = parseWorkspaceYaml(descriptorSource);
   const rendered = renderWorkspaceRuntimeFromWorkspace({
     workspace,
     workspaceId: revision.id,
@@ -367,7 +368,7 @@ export async function renderActiveWorkspaceRuntime(options: {
   return {
     ...rendered,
     snapshotPath,
-    descriptorBlob: revision.blob,
+    descriptorBlob: `sha256:${createHash("sha256").update(descriptorSource).digest("hex")}`,
     catalogBlob: (await repository.catalogBlob(revision.commit)).trim(),
   };
 }

backend/test/workspace-runtime-config-lease.test.ts

@@ -159,7 +159,7 @@ test("active workspace rendering is byte-identical to direct snapshot rendering"
 
   expect(active.renderedConfig).toBe(direct.renderedConfig);
   expect(active.workspaceRevision).toBe(f.revision.commit);
-  expect(active.descriptorBlob).toBe(f.revision.blob);
+  expect(active.descriptorBlob).toMatch(/^sha256:[0-9a-f]{64}$/);
   expect(active.catalogBlob).toMatch(/^[0-9a-f]{40}$/);
 });