fix: harden archive metrics and result retention

Derive archive operation identity from item-path provenance so equal basenames in different directories remain distinct, and keep unknown part counts at zero when no item provenance exists.

Prune finalized results only after their generation is no longer current or referenced, and add 80-package digest and individual delivery coverage to prove deterministic paging without event loss.

tests/notify-hooks.test.ts

@@ -348,6 +348,30 @@ describe("authoritative package completion", () => {
     expect(events.map((event) => event.type)).toEqual(["package_completed"]);
     expect(events[0].payload.title).toContain("Paket-Digest");
   });
+
+  it.each([
+    ["digest", 4],
+    ["individual", 80]
+  ] as const)("delivers 80 successful packages in %s mode without loss", async (mode, expectedEvents) => {
+    const { manager, session, events } = setup({ notifyPackageSuccessMode: mode });
+    const state = internal(manager);
+    for (let index = 0; index < 80; index += 1) {
+      const pkg = addPackage(session, ["completed"], `bulk-package-${String(index).padStart(2, "0")}`);
+      state.runPackageIds.add(pkg.id);
+      state.tryFinalizePackageResult(pkg.id);
+    }
+    if (mode === "digest") {
+      state.flushPackageSuccessDigest();
+    }
+    await state.notificationEnqueueChain;
+
+    expect(events).toHaveLength(expectedEvents);
+    expect(new Set(events.map((event) => event.id))).toHaveLength(expectedEvents);
+    if (mode === "digest") {
+      expect(events.map((event) => event.payload.fields.length)).toEqual([20, 20, 20, 20]);
+      expect(events.every((event) => event.payload.description === "80 Pakete abgeschlossen")).toBe(true);
+    }
+  });
 });
 
 describe("authoritative run completion", () => {
@@ -595,6 +619,7 @@ describe("authoritative run completion", () => {
     expect(completedRun?.payload.fields.some((field) => field.name === "Dateien" && field.value === "1 erfolgreich · 0 fehlgeschlagen · 0 abgebrochen")).toBe(true);
     expect(history).toHaveLength(1);
     expect(history[0].id).toBe(`hist-${pkg.id}-2`);
+    expect([...state.finalizedPackageResults.keys()].filter((key) => key.startsWith(`${pkg.id}:`))).toEqual([`${pkg.id}:2`]);
   });
 
   it("tracks a main postprocess task created by triggerPendingExtractions after start begins", async () => {