fix: complete requirements.txt and inference.py output correctness.

- Add faiss-cpu, rank-bm25, sentence-transformers, numpy to requirements.txt.
  (previously only pymupdf was listed; other deps were manual-install only)
- Cast score to float() before round() to avoid numpy type serialization errors.
- Pass expected_standards through _format_result for eval script compatibility.
- Update retrieval_results.json with expected_standards per query for eval.

data/processed/retrieval_results.json

@@ -46,7 +46,10 @@
         "matched_section": "Degree Of Whiteness"
       }
     ],
-    "latency_seconds": 0.0586
+    "latency_seconds": 0.024,
+    "expected_standards": [
+      "IS 269: 1989"
+    ]
   },
   {
     "id": "PUB-02",
@@ -95,7 +98,10 @@
         "matched_section": "Scope"
       }
     ],
-    "latency_seconds": 0.0478
+    "latency_seconds": 0.0168,
+    "expected_standards": [
+      "IS 383: 1970"
+    ]
   },
   {
     "id": "PUB-03",
@@ -144,7 +150,10 @@
         "matched_section": "Tests"
       }
     ],
-    "latency_seconds": 0.0448
+    "latency_seconds": 0.0165,
+    "expected_standards": [
+      "IS 458: 2003"
+    ]
   },
   {
     "id": "PUB-04",
@@ -193,7 +202,10 @@
         "matched_section": "Scope"
       }
     ],
-    "latency_seconds": 0.0452
+    "latency_seconds": 0.0161,
+    "expected_standards": [
+      "IS 2185 (Part 2): 1983"
+    ]
   },
   {
     "id": "PUB-05",
@@ -242,7 +254,10 @@
         "matched_section": "Scope"
       }
     ],
-    "latency_seconds": 0.0402
+    "latency_seconds": 0.0154,
+    "expected_standards": [
+      "IS 459: 1992"
+    ]
   },
   {
     "id": "PUB-06",
@@ -291,7 +306,10 @@
         "matched_section": "Scope"
       }
     ],
-    "latency_seconds": 0.0361
+    "latency_seconds": 0.0152,
+    "expected_standards": [
+      "IS 455: 1989"
+    ]
   },
   {
     "id": "PUB-07",
@@ -340,7 +358,10 @@
         "matched_section": "Physical Requirements"
       }
     ],
-    "latency_seconds": 0.0384
+    "latency_seconds": 0.0174,
+    "expected_standards": [
+      "IS 1489 (Part 2): 1991"
+    ]
   },
   {
     "id": "PUB-08",
@@ -389,7 +410,10 @@
         "matched_section": "Classification"
       }
     ],
-    "latency_seconds": 0.0352
+    "latency_seconds": 0.0167,
+    "expected_standards": [
+      "IS 3466: 1988"
+    ]
   },
   {
     "id": "PUB-09",
@@ -438,7 +462,10 @@
         "matched_section": "Design And Manufacture"
       }
     ],
-    "latency_seconds": 0.0432
+    "latency_seconds": 0.0178,
+    "expected_standards": [
+      "IS 6909: 1990"
+    ]
   },
   {
     "id": "PUB-10",
@@ -487,6 +514,9 @@
         "matched_section": "Delivery"
       }
     ],
-    "latency_seconds": 0.0333
+    "latency_seconds": 0.0156,
+    "expected_standards": [
+      "IS 8042: 1989"
+    ]
   }
 ]