W20: Tool Calling 闭环 + Stream+Tools + 回归测试 + session auto-save + ASan CI (W20.1-W20.6)

- W20.1: CLI tool_calls→execute→result→re-call 循环（5轮上限）
- W20.2: deepseek 流式 tool_calls 增量解析（configure 缓存，无 ABI break）
- W20.3: plugin_loader 回归测试 5 块 32 断言（路径/原子性/mock 日志）
- W20.4: plugin_loader ABI 契约校验（name/version/on_init 字段验证）
- W20.5: ASan/UBSan CMake preset + CI sanitizer job（PR-only Linux）
- W20.6: session auto-save（on_shutdown 写 %APPDATA%/dstalk/session.json）

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

CMakePresets.json

@@ -28,8 +28,8 @@
                 "value": "x64",
                 "strategy": "external"
             },
-            "toolchainFile": "generators\\conan_toolchain.cmake",
-            "binaryDir": "E:\\Prj2026\\AIGen2026\\dstalk\\build\\build\\Release"
+            "toolchainFile": "${sourceDir}/build/build/Release/generators/conan_toolchain.cmake",
+            "binaryDir": "${sourceDir}/build/build/Release"
         },
         {
             "name": "ci-release",
@@ -42,6 +42,18 @@
             },
             "toolchainFile": "${sourceDir}/build/Release/conan_toolchain.cmake",
             "binaryDir": "${sourceDir}/build/ci"
+        },
+        {
+            "name": "ci-sanitize",
+            "inherits": "conan-release",
+            "displayName": "CI Sanitizer (ASan+UBSan)",
+            "description": "AddressSanitizer + UndefinedBehaviorSanitizer Linux clang CI build",
+            "toolchainFile": "${sourceDir}/build/Release/conan_toolchain.cmake",
+            "binaryDir": "${sourceDir}/build/ci-sanitize",
+            "cacheVariables": {
+                "CMAKE_C_FLAGS": "-fsanitize=address,undefined -fno-omit-frame-pointer",
+                "CMAKE_CXX_FLAGS": "-fsanitize=address,undefined -fno-omit-frame-pointer"
+            }
         }
     ],
     "buildPresets": [
@@ -54,6 +66,11 @@
             "name": "ci-release",
             "configurePreset": "ci-release",
             "jobs": 0
+        },
+        {
+            "name": "ci-sanitize",
+            "configurePreset": "ci-sanitize",
+            "jobs": 0
         }
     ],
     "testPresets": [
@@ -73,6 +90,13 @@
             "execution": {
                 "jobs": 0
             }
+        },
+        {
+            "name": "ci-sanitize",
+            "configurePreset": "ci-sanitize",
+            "execution": {
+                "jobs": 0
+            }
         }
     ]
 }