refactor: 目录名统一小写（BuildFlow.Host→build-flow.host，BuildFlow.Shared→build-flow.shared）

- src/BuildFlow.Host → src/build-flow.host
- src/shared/BuildFlow.Shared → src/shared/build-flow.shared
- 同步改 slnx/ProjectReference/run-dev.sh 路径
- csproj 文件名 + AssemblyName/RootNamespace 保持 PascalCase（.NET 规范）
- build 0/0

BuildFlow.slnx

@@ -1,7 +1,7 @@
 <Solution>
   <Folder Name="/src/">
-    <Project Path="src/BuildFlow.Host/BuildFlow.Host.csproj" />
-    <Project Path="src/shared/BuildFlow.Shared/BuildFlow.Shared.csproj" />
+    <Project Path="src/build-flow.host/BuildFlow.Host.csproj" />
+    <Project Path="src/shared/build-flow.shared/BuildFlow.Shared.csproj" />
   </Folder>
   <Folder Name="/src/modules/rag/">
     <Project Path="src/modules/rag/Domain/BuildFlow.Domain.csproj" />

run-dev.sh

@@ -24,6 +24,6 @@ fi
 # 3. dotnet 的层级配置用 __ 双下划线，.env 里已用 ConnectionStrings__Rag 等变量定义各库连接串，
 #    .NET 配置系统会自动读取环境变量覆盖 appsettings.json，无需在此重复 export。
 
-# 4. 启动 BuildFlow Host（路径为 src/BuildFlow.Host）
-cd "$SCRIPT_DIR/src/BuildFlow.Host"
+# 4. 启动 BuildFlow Host（路径为 src/build-flow.host）
+cd "$SCRIPT_DIR/src/build-flow.host"
 exec dotnet run --urls http://localhost:5200

src/BuildFlow.Host/Endpoints/rag/Chat/CreateConversationRequest.cs

@@ -1,8 +0,0 @@
-namespace BuildFlow.Host.Endpoints.rag.Chat;
-
-/// <summary>
-/// Create会话请求体。
-/// </summary>
-public record CreateConversationRequest(string Title);
-
-/// <summary>创建会话请求校验。</summary>

src/build-flow.host/Endpoints/rag/Chat/CreateConversationRequest.cs

@@ -0,0 +1,6 @@
+namespace BuildFlow.Host.Endpoints.rag.Chat;
+
+/// <summary>
+/// Create会话请求体。
+/// </summary>
+public record CreateConversationRequest(string Title);