Wave 9: fix audit findings, harden ABI, deduplicate config (W12.1-W12.6)

- W12.1 context_plugin (engineer-zhou): wrap C ABI surface in try/catch,
  add OOM-safe strdup_message_fields helper, make g_max_tokens drive
  message-count trim (option A).
- W12.2 config refactor (architect-lin): introduce
  plugins/config/include/toml_parse.h to eliminate 74-line parser
  duplication; config_plugin delegates to host->config_get/set,
  collapsing the dual-store data island; ConfigStore::get() now copies
  via thread_local std::string to remove c_str() dangling under
  concurrent set(). Zero ABI changes.
- W12.3 CLI command parsing (engineer-zhao): guard /clear and /context
  on missing session service; refactor /file dispatch so bare
  /file write hits usage instead of unknown-command.
- W12.4 build path unification (devops-hu): set per-target
  RUNTIME_OUTPUT_DIRECTORY on dstalk-cli; remove stale
  build/dstalk-cli/dstalk-cli.exe so build/bin/ is the sole binary.
- W12.5 STATUS.md auto-refresh (engineer-li): run W11.6 script to
  regenerate STATUS from live profile/group data.
- W12.6 plugin-abi.md (writer-deng): add §8 exception safety across
  ABI boundary and §9 string return lifetime; reference real
  audit-found violations as anti-examples.

Verified: cmake build 0 error 0 warning, ctest 4/4 pass.

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

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

agents/engineer-zhao/profile.md

@@ -42,3 +42,6 @@ current_groups:
   - date: 2026-05-27
     event: "W11.4: 实现管道输入支持(grp-cli-ux B3)，pipe_mode检测_isatty→读取全部stdin→单次chat→退出；空输入返回1提示empty prompt；0 error 0 warning编译通过；4/4测试100% pass"
     rating: A
+  - date: 2026-05-27
+    event: "W12.3: 修复3个命令解析bug(BUG-2 /clear空session谎报成功→stderr守卫; BUG-3 /context空session静默→else分支stderr; BUG-4 /file write裸命令→统一token解析入口)，build 0 error 0 warning，4/4 test pass"
+    rating: completed