core(M4): fglctl, fglair-discover, README библиотеки; M5 — вне скоупа core-релиза

- README.md (корень): сборка POSIX/ESP-IDF-компонентом, тесты, получение
  ключа (fglair-discover), примеры fglctl; planned-компоненты помечены.
- examples/cli/fglctl.cpp: monitor/get/set/status на публичном API
  (batch GET шаблона, конверсии, wait_online, логи в stderr, exit-коды;
  сборка с -Wall -Wextra -Werror).
- tools/fglair-discover: облачный provisioning (eu/us/cn, endpoints и
  app_id/secret из PROTOCOL §7), --format json|esphome-secrets, --out 0600,
  обработка URLError/KeyError; stdlib-only.
- tests/tools/test_fglair_discover.py: мок-облако (http.server), 4 теста,
  ctest tools_fglair_discover.
- docs/reports/M4_SOAK.md: 60-мин soak на AP-WC1E — 0 рассинхронов,
  33/33 свойства (вкл. строковые), 273 опроса модуля, pushes_bad=0;
  24-ч прогон — приёмочный шаг перед релизом.
- План: M4 ✅; M5 (FglHub/mDNS) — ВНЕ СКОУПА core-релиза.
- Гигиена: config_kata.json (корень+docs/legacy) в .gitignore; MQTT-креды
  из docs/legacy/run.sh заменены плейсхолдером (история чистится отдельно).
- Фиксы ревью: mock арм fail-pushes после активации (флейк san-сборки);
  fglctl: валидация strtoll (abc/99 — отказ, exit!=0), чтение config с
  предупреждением об обрезке, Config{} вместо memset; discover: 0600.
CI: 11/11 ×3 (gcc-Rel, gcc-ASan/UBSan, clang); ESP-IDF esp32 build complete.

README.md

@@ -0,0 +1,106 @@
+# fglair-core
+
+Local-control library for Fujitsu General air conditioners (FGLair / Ayla LAN
+protocol). One C++20 codebase — Linux and ESP-IDF (ESP32) — with the full
+protocol reconstructed from the official APK and verified on real hardware.
+
+See [`docs/PROTOCOL.md`](docs/PROTOCOL.md) for the protocol reference and
+[`docs/PLAN_CORE_LIBRARY.md`](docs/PLAN_CORE_LIBRARY.md) for the design.
+
+## Layout
+
+```
+include/fgl-aircon/   public API (types, templates, session, C API for cffi)
+src/ayla/             Ayla LAN protocol: crypto, envelope, HTTP, session loop
+src/aircon/           property templates A/B/F, conversions, API implementation
+components/          ESPHome external component      (planned, docs/PLAN_ESPHOME.md)
+custom_components/   Home Assistant custom component (planned, docs/PLAN_HOME_ASSISTANT.md)
+tests/               ayla (protocol), aircon (conversions), tools
+examples/cli/        fglctl — sample CLI
+tools/               fglair-discover, protocol probes
+```
+
+## Build (Linux / POSIX)
+
+Requirements: CMake ≥ 3.16, Ninja (or Make), g++/clang with C++20, Mbed TLS
+(system `libmbedcrypto`; otherwise it is fetched and built automatically).
+
+```sh
+cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
+cmake --build build
+# CLI:
+./build/fglctl <config.json> status
+```
+
+## Build (ESP-IDF component)
+
+The repository root is an ESP-IDF component. Put it on `EXTRA_COMPONENT_DIRS`
+(or copy into your project's `components/`):
+
+```cmake
+set(EXTRA_COMPONENT_DIRS "/path/to/aircon")
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(my_app)
+```
+
+```cmake
+# main/CMakeLists.txt
+idf_component_register(SRCS "main.cpp" PRIV_REQUIRES aircon)
+```
+
+```cpp
+#include "fgl-aircon/session.hpp"
+extern "C" void app_main() {
+  fgl::aircon::Config cfg{};
+  cfg.host = "ac.local";      // DNS name or IP
+  cfg.dsn = "...";            // from fglair-discover
+  cfg.lanip_key = "...";      // from fglair-discover (static per module)
+  cfg.lanip_key_id = 12345;
+  cfg.tmpl = fgl::aircon::template_detect("AP-WC1E");
+  fgl::aircon::Callbacks cbs{};
+  auto* s = fgl::aircon::Session::create(cfg, cbs);
+  s->start();
+}
+```
+
+Tested with ESP-IDF v5.5 (esp32); no Arduino support.
+
+## Tests
+
+```sh
+./scripts/ci.sh          # Release + ASan/UBSan + clang builds, all tests
+# or:
+ctest --test-dir build --output-on-failure
+```
+
+`tests/ayla` covers the protocol (KDF vectors from the APK, envelope, HTTP,
+session scenarios against a Python mock of the module).
+`tests/aircon` covers template tables and conversions.
+No hardware needed.
+
+## Getting the key (`lanip_key`)
+
+The key is static (baked into the AC module; only served by the Ayla cloud):
+
+```sh
+tools/fglair-discover --region eu --email you@example.com
+# prints one config JSON per device, or a secrets block:
+tools/fglair-discover --region eu --email you@example.com --format esphome-secrets
+```
+
+## fglctl
+
+```sh
+fglctl config.json status                  # session check + cached temperature
+fglctl config.json monitor 60              # follow all events for 60 s
+fglctl config.json get OperationMode FanSpeed
+fglctl config.json set AdjustTemperature 220   # 22.0 °C (unit 0.1 °C)
+```
+
+Values are in API units: temperatures in 0.1 °C, `DisplayTemperature`
+converted from the module's 0.01 °C+5000 format.
+
+## License / provenance
+
+Protocol documentation and code reconstructed from the FGLair 3.4.3 APK for
+interoperability; `third_party/jsmn` is MIT.