fix(plan): edit/add the clicked record + layer-aware add in exception mode

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/__tests__/plan.test.ts

@@ -247,6 +247,75 @@ describe("plan.service.resolveGrid", () => {
     expect(cells[adminUserId]["2099-06-02"][0]?.note).toBe(`${N}B`);
     expect(cells[adminUserId]["2099-06-03"][0]?.note).toBe(`${N}A`);
   });
+
+  it("stacks additive entries newest-first and caps the day at MAX_RECORDS_PER_CELL", async () => {
+    // Two entries cover 2099-06-12 → both appear, newest-first. A 3rd entry
+    // covering the same day and a 4th overlapping one push past the cap, so the
+    // day must still return exactly 3 (mirrors resolveCell's cap behaviour).
+    //
+    // created_at is @db.Timestamp(0) (second precision, MySQL TIMESTAMP range
+    // tops out at 2038), so rows created in the same second tie on the
+    // `created_at desc` sort. We set explicit, distinct in-range created_at
+    // values so the newest-first assertion is deterministic.
+    await prisma.work_plan_entries.create({
+      data: {
+        user_id: adminUserId,
+        date_from: new Date("2099-06-11"),
+        date_to: new Date("2099-06-12"),
+        category: "work",
+        note: `${N}g1`,
+        created_by: adminUserId,
+        created_at: new Date("2037-06-01T08:00:00.000Z"),
+      },
+    });
+    await prisma.work_plan_entries.create({
+      data: {
+        user_id: adminUserId,
+        date_from: new Date("2099-06-12"),
+        date_to: new Date("2099-06-12"),
+        category: "work",
+        note: `${N}g2`,
+        created_by: adminUserId,
+        created_at: new Date("2037-06-01T09:00:00.000Z"), // newer than g1
+      },
+    });
+    // Two-entry day: assert length 2 and newest-first ordering.
+    const twoDay = await resolveGrid([adminUserId], "2099-06-11", "2099-06-12");
+    expect(twoDay[adminUserId]["2099-06-12"].length).toBe(2);
+    expect(twoDay[adminUserId]["2099-06-12"][0].note).toBe(`${N}g2`); // newest first
+    // Day with no second entry stays single.
+    expect(twoDay[adminUserId]["2099-06-11"].length).toBe(1);
+
+    // Add a 3rd and a 4th overlapping entry on 2099-06-12 to exceed the cap.
+    await prisma.work_plan_entries.create({
+      data: {
+        user_id: adminUserId,
+        date_from: new Date("2099-06-12"),
+        date_to: new Date("2099-06-12"),
+        category: "work",
+        note: `${N}g3`,
+        created_by: adminUserId,
+        created_at: new Date("2037-06-01T10:00:00.000Z"),
+      },
+    });
+    await prisma.work_plan_entries.create({
+      data: {
+        user_id: adminUserId,
+        date_from: new Date("2099-06-12"),
+        date_to: new Date("2099-06-12"),
+        category: "work",
+        note: `${N}g4`,
+        created_by: adminUserId,
+        created_at: new Date("2037-06-01T11:00:00.000Z"),
+      },
+    });
+    const cappedDay = await resolveGrid(
+      [adminUserId],
+      "2099-06-12",
+      "2099-06-12",
+    );
+    expect(cappedDay[adminUserId]["2099-06-12"].length).toBe(3);
+  });
 });
 
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