Wave 5+6: plugin ABI hardening, build modernization, ABI/security docs

Wave 5 (9 parallel agents):
- W1.1 atomic diag callback + DLL handle release on shutdown (lin)
- W2.1 unify cross-DLL heap discipline (host->alloc/free/strdup) (chen)
- W2.2 secure_zero api_key on shutdown for deepseek/anthropic (cao)
- W3 CMake modernization: target-based cxx_std_20, dstalk_boost_config
  INTERFACE lib, root-level RUNTIME_OUTPUT_DIRECTORY (hu)
- W4 GitHub Actions CI with dynamic Linux/Windows matrix (ma)
- W5.1 SSE buffer_body to cut peak memory ~67% on 32K streams (zhou)
- W6.1 LSP JSON-RPC frame parser hardened against header reordering (sun)
- W7 smoke test: copy plugin DLLs post-build + Boost.JSON src.hpp fix
  for full 9-plugin load coverage (wang)
- W8.1 README slimmed 398->92, Diataxis docs/ skeleton (deng)

Wave 6 (6 parallel agents):
- W9.1 docs/explanation: architecture + plugin-lifecycle (deng)
- W9.3 log credential leak audit (0 vulns, audit trail in
  docs/explanation/security-logging.md) (cao)
- W9.4 docs/reference/plugin-abi.md - 7-point ABI contract (lin)
- W9.6 CLI /history command + status integration (zhao)
- W9.8 plugin_loader fault tolerance: per-plugin failure no longer
  aborts dstalk_init (huang)
- W9.10 host_api unit tests: tests/host_api_test.cpp, 8 cases (liu)

CEO oversight (preexisting bugs fixed during Wave 5 verification):
- lsp_plugin.cpp:449 forward decl mismatch (int vs void)
- tools_plugin.cpp:109 missing forward decl

Multi-agent collaboration framework:
- agents/WORKFLOW.md: 6-stage protocol, two-tier governance,
  prompt template, technical constraints registry

Build: cmake --build 0 error / 0 warning. Tests: 2/2 100% pass.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

plugins/deepseek/CMakeLists.txt

@@ -9,21 +9,11 @@ add_library(plugin-deepseek SHARED
     src/deepseek_plugin.cpp
 )
 
-target_include_directories(plugin-deepseek PRIVATE
-    ${CMAKE_SOURCE_DIR}/dstalk-core/include
-)
-
 target_link_libraries(plugin-deepseek PRIVATE dstalk)
 
 # Boost.JSON 用于构建/解析请求和响应
 find_package(Boost REQUIRED CONFIG)
-target_link_libraries(plugin-deepseek PRIVATE boost::boost)
-
-target_compile_definitions(plugin-deepseek PRIVATE
-    BOOST_ALL_NO_LIB
-    BOOST_ERROR_CODE_HEADER_ONLY
-    BOOST_JSON_HEADER_ONLY
-)
+target_link_libraries(plugin-deepseek PRIVATE boost::boost dstalk_boost_config)
 
 set_target_properties(plugin-deepseek PROPERTIES
     PREFIX ""

plugins/deepseek/src/deepseek_plugin.cpp

@@ -2,6 +2,7 @@
 #include "dstalk/dstalk_services.h"
 
 #include <boost/json.hpp>
+#include <boost/json/src.hpp>
 #include <cstring>
 #include <string>
 
@@ -27,6 +28,14 @@ struct PluginConfig {
 };
 static PluginConfig g_cfg;
 
+// ============================================================================
+// 安全擦除：用 volatile 写零循环防止编译器优化
+// ============================================================================
+static void secure_zero(void* p, size_t n) {
+    volatile char* vp = (volatile char*)p;
+    while (n--) *vp++ = 0;
+}
+
 // ============================================================================
 // 辅助：从 base_url 提取 host 和 target
 // ============================================================================
@@ -450,6 +459,8 @@ static int on_init(const dstalk_host_api_t* host)
 static void on_shutdown()
 {
     if (g_host) g_host->log(DSTALK_LOG_INFO, "[deepseek] shutdown");
+    secure_zero(g_cfg.api_key.data(), g_cfg.api_key.size());
+    g_cfg.api_key.clear();
     g_http = nullptr;
     g_config = nullptr;
     g_host = nullptr;