fix(process): harden capture validation and cleanup

src/application/ProcessCaptureError.ts

@@ -0,0 +1,6 @@
+import { AnalysisError } from "../domain/errors.js";
+
+/** Typed application failure produced by controlled process capture. */
+export class ProcessCaptureError extends AnalysisError {
+  readonly _tag = "ProcessCaptureError";
+}