Extract groombook/api from monorepo with CI workflow

- Add source code from apps/api
- Add packages/db and packages/types workspace dependencies
- Add GitHub Actions CI workflow (lint, typecheck, test, docker)
- Generate pnpm-lock.yaml
- Add .gitignore

Co-Authored-By: Paperclip <noreply@paperclip.ing>

src/__tests__/slots.test.ts

@@ -0,0 +1,116 @@
+import { describe, it, expect } from "vitest";
+import {
+  generateAvailableSlots,
+  BUSINESS_START_HOUR,
+  BUSINESS_END_HOUR,
+} from "../lib/slots.js";
+
+const DATE = "2026-03-18";
+const G1 = "groomer-1";
+const G2 = "groomer-2";
+
+function utc(h: number, m = 0): Date {
+  const d = new Date(`${DATE}T00:00:00Z`);
+  d.setUTCHours(h, m, 0, 0);
+  return d;
+}
+
+describe("generateAvailableSlots", () => {
+  it("returns slots within business hours", () => {
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [G1],
+      booked: [],
+    });
+    expect(slots.length).toBeGreaterThan(0);
+    slots.forEach((s) => {
+      const h = new Date(s).getUTCHours();
+      expect(h).toBeGreaterThanOrEqual(BUSINESS_START_HOUR);
+      expect(h).toBeLessThan(BUSINESS_END_HOUR);
+    });
+  });
+
+  it("returns correct count of 60-min slots across 8-hour window", () => {
+    // 09:00–17:00 = 8 hours → 8 one-hour slots
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [G1],
+      booked: [],
+    });
+    expect(slots).toHaveLength(8);
+  });
+
+  it("returns empty array when no groomers", () => {
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [],
+      booked: [],
+    });
+    expect(slots).toHaveLength(0);
+  });
+
+  it("excludes slots blocked by a booking", () => {
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [G1],
+      booked: [{ staffId: G1, startTime: utc(9), endTime: utc(10) }],
+    });
+    expect(slots).not.toContain(new Date(`${DATE}T09:00:00.000Z`).toISOString());
+    expect(slots).toContain(new Date(`${DATE}T10:00:00.000Z`).toISOString());
+  });
+
+  it("keeps slot available when only the other groomer is booked", () => {
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [G1, G2],
+      booked: [{ staffId: G1, startTime: utc(9), endTime: utc(10) }],
+    });
+    // G2 is free at 09:00 so slot should still appear
+    expect(slots).toContain(new Date(`${DATE}T09:00:00.000Z`).toISOString());
+  });
+
+  it("excludes a slot only when ALL groomers are booked", () => {
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [G1, G2],
+      booked: [
+        { staffId: G1, startTime: utc(9), endTime: utc(10) },
+        { staffId: G2, startTime: utc(9), endTime: utc(10) },
+      ],
+    });
+    expect(slots).not.toContain(new Date(`${DATE}T09:00:00.000Z`).toISOString());
+  });
+
+  it("correctly handles a booking that partially overlaps a slot", () => {
+    // Booking 09:30–10:30 should block the 09:00 and 10:00 slots for G1
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 60,
+      groomerIds: [G1],
+      booked: [{ staffId: G1, startTime: utc(9, 30), endTime: utc(10, 30) }],
+    });
+    expect(slots).not.toContain(new Date(`${DATE}T09:00:00.000Z`).toISOString());
+    expect(slots).not.toContain(new Date(`${DATE}T10:00:00.000Z`).toISOString());
+    expect(slots).toContain(new Date(`${DATE}T11:00:00.000Z`).toISOString());
+  });
+
+  it("does not generate a slot that would exceed business hours end", () => {
+    // 30-min slots: last valid start is 16:30 (ends at 17:00)
+    const slots = generateAvailableSlots({
+      dateStr: DATE,
+      durationMinutes: 30,
+      groomerIds: [G1],
+      booked: [],
+    });
+    const last = slots[slots.length - 1];
+    expect(last).toBeDefined();
+    expect(new Date(last!).getUTCHours()).toBe(16);
+    expect(new Date(last!).getUTCMinutes()).toBe(30);
+  });
+});