test(students): add unit, integration and e2e tests for /students (#109)

- unit: fixture shapes, mock API (GET/POST/PUT/DELETE), mock DB operations
- integration: real DB CRUD via testDb (list, filter, create, get, update, delete)
- e2e: handler calls directly with mock FreshContext + real DB
  covers auth (employee vs non-employee), 400/403/404 cases
- adds test:e2e deno task and CI step
- adds tests/helpers/handler.ts with makeEmployeeContext, makeContextWithAffiliation,
  makeGetRequest, makeJsonRequest utilities

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/integration/students_test.ts

@@ -0,0 +1,173 @@
+// #109 - Integration tests for /students endpoints
+// Teste les opérations DB directement avec une vraie base de données
+
+import { assertEquals, assertExists } from "@std/assert";
+import {
+  seedPromotions,
+  seedStudents,
+  testDb,
+  truncateAll,
+} from "../helpers/db_integration.ts";
+import { students } from "$root/databases/schema.ts";
+import { eq } from "npm:drizzle-orm@0.45.2";
+
+Deno.test({
+  name: "integration students: list all students",
+  async fn() {
+    await truncateAll();
+    await seedPromotions([{ id: "PEIP1-2024" }]);
+    await seedStudents([
+      { nom: "Dupont", prenom: "Jean", idPromo: "PEIP1-2024" },
+      { nom: "Martin", prenom: "Alice", idPromo: "PEIP1-2024" },
+    ]);
+
+    const rows = await testDb.select().from(students);
+    assertEquals(rows.length, 2);
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: filter by idPromo",
+  async fn() {
+    await truncateAll();
+    await seedPromotions([{ id: "PEIP1-2024" }, { id: "PEIP2-2024" }]);
+    await seedStudents([
+      { nom: "Dupont", prenom: "Jean", idPromo: "PEIP1-2024" },
+      { nom: "Martin", prenom: "Alice", idPromo: "PEIP1-2024" },
+      { nom: "Durand", prenom: "Claire", idPromo: "PEIP2-2024" },
+    ]);
+
+    const rows = await testDb
+      .select()
+      .from(students)
+      .where(eq(students.idPromo, "PEIP1-2024"));
+    assertEquals(rows.length, 2);
+    assertEquals(rows.every((s) => s.idPromo === "PEIP1-2024"), true);
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: create and retrieve by numEtud",
+  async fn() {
+    await truncateAll();
+    await seedPromotions([{ id: "INFO3-2024" }]);
+
+    const [created] = await testDb
+      .insert(students)
+      .values({ nom: "Leroy", prenom: "Paul", idPromo: "INFO3-2024" })
+      .returning();
+
+    assertExists(created.numEtud);
+
+    const row = await testDb
+      .select()
+      .from(students)
+      .where(eq(students.numEtud, created.numEtud))
+      .then((r) => r[0] ?? null);
+
+    assertExists(row);
+    assertEquals(row.nom, "Leroy");
+    assertEquals(row.idPromo, "INFO3-2024");
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: get by numEtud returns null when not found",
+  async fn() {
+    await truncateAll();
+
+    const row = await testDb
+      .select()
+      .from(students)
+      .where(eq(students.numEtud, 999999))
+      .then((r) => r[0] ?? null);
+
+    assertEquals(row, null);
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: update student fields",
+  async fn() {
+    await truncateAll();
+    await seedPromotions([{ id: "INFO3-2024" }, { id: "INFO4-2024" }]);
+    const [s] = await seedStudents([
+      { nom: "Petit", prenom: "Hugo", idPromo: "INFO3-2024" },
+    ]);
+
+    const [updated] = await testDb
+      .update(students)
+      .set({ nom: "Grand", idPromo: "INFO4-2024" })
+      .where(eq(students.numEtud, s.numEtud))
+      .returning();
+
+    assertEquals(updated.nom, "Grand");
+    assertEquals(updated.idPromo, "INFO4-2024");
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: delete student",
+  async fn() {
+    await truncateAll();
+    await seedPromotions([{ id: "INFO3-2024" }]);
+    const [s] = await seedStudents([
+      { nom: "Thomas", prenom: "Eva", idPromo: "INFO3-2024" },
+    ]);
+
+    await testDb.delete(students).where(eq(students.numEtud, s.numEtud));
+
+    const row = await testDb
+      .select()
+      .from(students)
+      .where(eq(students.numEtud, s.numEtud))
+      .then((r) => r[0] ?? null);
+
+    assertEquals(row, null);
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: update non-existent student returns empty",
+  async fn() {
+    await truncateAll();
+
+    const result = await testDb
+      .update(students)
+      .set({ nom: "Ghost" })
+      .where(eq(students.numEtud, 999999))
+      .returning();
+
+    assertEquals(result.length, 0);
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});
+
+Deno.test({
+  name: "integration students: delete non-existent student returns empty",
+  async fn() {
+    await truncateAll();
+
+    const result = await testDb
+      .delete(students)
+      .where(eq(students.numEtud, 999999))
+      .returning();
+
+    assertEquals(result.length, 0);
+  },
+  sanitizeResources: false,
+  sanitizeOps: false,
+});