feat(agent): group ingestion proposals by learning

contracts/service-v1.json

@@ -1162,7 +1162,7 @@
       "name": "source_extract"
     },
     {
-      "description": "Read a bounded normalized text slice and its source offset map.",
+      "description": "Read a bounded normalized text slice and optionally its original-source offset map.",
       "input_schema": {
         "properties": {
           "block_id": {
@@ -1173,6 +1173,11 @@
             "title": "Extraction Id",
             "type": "string"
           },
+          "include_original_mapping": {
+            "default": false,
+            "title": "Include Original Mapping",
+            "type": "boolean"
+          },
           "length": {
             "title": "Length",
             "type": "integer"