refactor: 架构重组 — doc/bot → core/infra，新增 Agent 调度模块

- src/doc/ 拆分为 src/core/extraction/, matching/, validation/（核心业务逻辑）
- src/bot/ 重命名为 src/infra/browser/（浏览器自动化基础设施）
- fill_consumable_doc.py → src/infra/documents/consumable.py
- 新增 Agent 调度模块：coordinator.py, events.py, session.py，重构 orchestrator.py
- 更新 AGENTS.md、README.md 及所有子目录 README

tests/test_llm_extractor.py

@@ -14,7 +14,7 @@ from pathlib import Path
 
 import pytest
 
-from src.doc.llm_extractor import (
+from src.core.extraction import (
     _image_to_base64,
     extract_document,
     parse_json_response,
@@ -131,7 +131,7 @@ class TestExtractDocument:
         def fake_query(system_prompt, text, image_b64, max_tokens=4096):
             return response_text
 
-        monkeypatch.setattr("src.doc.llm_extractor._llm_query_multimodal", fake_query)
+        monkeypatch.setattr("src.core.extraction.llm_extractor._llm_query_multimodal", fake_query)
 
     def test_success(self, tmp_path: Path, monkeypatch):
         img_path = tmp_path / "card.png"
@@ -156,7 +156,7 @@ class TestExtractDocument:
         def fake_query(system_prompt, text, image_b64, max_tokens=4096):
             raise RuntimeError("模型不可用")
 
-        monkeypatch.setattr("src.doc.llm_extractor._llm_query_multimodal", fake_query)
+        monkeypatch.setattr("src.core.extraction.llm_extractor._llm_query_multimodal", fake_query)
         with pytest.raises(RuntimeError, match="模型不可用"):
             extract_document(img_path)
 
@@ -193,7 +193,7 @@ class TestExtractDocument:
             received_b64 = image_b64s
             return json.dumps({K_CARD_DATE: "2026-01-01", K_CARD_NO: "0000", K_CARD_AMOUNT: "100"})
 
-        monkeypatch.setattr("src.doc.llm_extractor._llm_query_multimodal", capture_b64)
+        monkeypatch.setattr("src.core.extraction.llm_extractor._llm_query_multimodal", capture_b64)
         extract_document(img_path)
 
         assert received_b64 is not None