phase-10.5: test case fixes and updated postman collection

tests/bond-scorer.test.ts

@@ -84,6 +84,28 @@ test('BondScorer', async (t) => {
     assert.ok(resultLong.audit?.passedGates);
   });
 
+  await t.test('returns structured tier (P0.3)', () => {
+    const good: BondMetrics = {
+      ytm: 7.5, // 7.5% vs ~4% risk-free → wide spread
+      duration: 5,
+      creditRating: 'A',
+      creditRatingNumeric: 8,
+    };
+    const pass = BondScorer.score(good, DEFAULT_RULES);
+    assert.equal(pass.tier, 'PASS');
+    assert.equal(typeof pass.score, 'number');
+
+    const junk: BondMetrics = {
+      ytm: 8,
+      duration: 5,
+      creditRating: 'CCC',
+      creditRatingNumeric: 4, // below investment-grade gate
+    };
+    const reject = BondScorer.score(junk, DEFAULT_RULES);
+    assert.equal(reject.tier, 'REJECT');
+    assert.equal(reject.score, null);
+  });
+
   await t.test('handles null/undefined metrics gracefully', () => {
     const metrics = {
       ytm: null,