refactor: generatePlan returns {assignments, skippedDates}

tests/algorithm.test.mjs

@@ -35,15 +35,15 @@ function emp(id, constraints = {}) {
 // generatePlan — basic assignment
 {
   const result = generatePlan(['2026-04-01'], [emp('alice'), emp('bob')], [], fixed);
-  assert.equal(result.length, 1, 'One workday → one assignment');
-  assert.ok(['alice','bob'].includes(result[0].employeeId), 'Assigned to alice or bob');
+  assert.equal(result.assignments.length, 1, 'One workday → one assignment');
+  assert.ok(['alice','bob'].includes(result.assignments[0].employeeId), 'Assigned to alice or bob');
 }
 
 // neverDays blocks employee
 {
   // 2026-04-01 is Wednesday (3)
   const result = generatePlan(['2026-04-01'], [emp('alice', {neverDays:[3]}), emp('bob')], [], fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice blocked on Wednesday → bob assigned');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice blocked on Wednesday → bob assigned');
 }
 
 // onlyDays restricts to specific days
@@ -51,7 +51,7 @@ function emp(id, constraints = {}) {
   // 2026-04-01 = Wednesday (3), 2026-04-02 = Thursday (4)
   const employees = [emp('alice', {onlyDays:[3]}), emp('bob')];
   const result = generatePlan(['2026-04-01','2026-04-02'], employees, [], fixed);
-  const aliceOnThursday = result.find(r => r.date === '2026-04-02' && r.employeeId === 'alice');
+  const aliceOnThursday = result.assignments.find(r => r.date === '2026-04-02' && r.employeeId === 'alice');
   assert.ok(!aliceOnThursday, 'alice with onlyDays:[3] not assigned on Thursday');
 }
 
@@ -62,7 +62,7 @@ function emp(id, constraints = {}) {
     emp('bob')
   ];
   const result = generatePlan(['2026-04-01'], employees, [], fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice on vacation → bob assigned');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice on vacation → bob assigned');
 }
 
 // maxPerMonth cap
@@ -70,7 +70,7 @@ function emp(id, constraints = {}) {
   const days = ['2026-04-01','2026-04-02','2026-04-03'];
   const employees = [emp('alice', {maxPerMonth:1}), emp('bob'), emp('clara')];
   const result = generatePlan(days, employees, [], fixed);
-  const aliceCount = result.filter(r => r.employeeId === 'alice').length;
+  const aliceCount = result.assignments.filter(r => r.employeeId === 'alice').length;
   assert.ok(aliceCount <= 1, 'alice maxPerMonth=1 → assigned at most once');
 }
 
@@ -80,14 +80,14 @@ function emp(id, constraints = {}) {
   const history = [{date:'2026-04-02', employeeId:'alice', manual:false}];
   const employees = [emp('alice', {minGapDays:5}), emp('bob')];
   const result = generatePlan(['2026-04-06'], employees, history, fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice within minGap (4<5) → bob assigned');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice within minGap (4<5) → bob assigned');
 }
 
 // No candidates → day skipped
 {
   // 2026-04-01 = Wednesday (3), only employee blocked
   const result = generatePlan(['2026-04-01'], [emp('alice', {neverDays:[3]})], [], fixed);
-  assert.equal(result.length, 0, 'No candidate → day skipped');
+  assert.equal(result.assignments.length, 0, 'No candidate → day skipped');
 }
 
 // Fairness: less history = higher priority
@@ -96,7 +96,7 @@ function emp(id, constraints = {}) {
     date: '2026-04-0' + i, employeeId: 'alice', manual: false
   }));
   const result = generatePlan(['2026-05-04'], [emp('alice'), emp('bob')], history, fixed);
-  assert.equal(result[0].employeeId, 'bob', 'bob (0 history) beats alice (5 history)');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'bob (0 history) beats alice (5 history)');
 }
 
 // companyClosures excluded from workdays
@@ -112,13 +112,13 @@ function emp(id, constraints = {}) {
   // Both have same history (0) — alice's score gets -5 penalty, bob wins
   const employees = [emp('alice', {lowPriorityDays:[3]}), emp('bob')];
   const result = generatePlan(['2026-04-01'], employees, [], fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice low priority on Wednesday → bob wins');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice low priority on Wednesday → bob wins');
 }
 
 // manual: false on auto-assigned entries
 {
   const result = generatePlan(['2026-04-01'], [emp('alice')], [], fixed);
-  assert.equal(result[0].manual, false, 'auto-assignment sets manual: false');
+  assert.equal(result.assignments[0].manual, false, 'auto-assignment sets manual: false');
 }
 
 console.log('All algorithm tests passed.');