Add POOL_INTEGRATION.md (pool migration spec); restore doc/build

- POOL_INTEGRATION.md: exact job/submit format, pool-side validation &
  scoring on the SHA256D pow-hash, and a zero-downtime dual-accept rollout
  plan (deploy dual-accept pool before announcing drg-xmrig).
- Restore doc/build/ docs removed during the initial copy.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

doc/build/CMAKE_OPTIONS.md

@@ -0,0 +1,41 @@
+# CMake options
+**Recent version of this document: https://xmrig.com/docs/miner/cmake-options**
+
+## Algorithms
+
+* **`-DWITH_CN_LITE=OFF`** disable all CryptoNight-Lite algorithms (`cn-lite/0`, `cn-lite/1`).
+* **`-DWITH_CN_HEAVY=OFF`** disable all CryptoNight-Heavy algorithms (`cn-heavy/0`, `cn-heavy/xhv`, `cn-heavy/tube`).
+* **`-DWITH_CN_PICO=OFF`** disable CryptoNight-Pico algorithm (`cn-pico`).
+* **`-DWITH_RANDOMX=OFF`** disable RandomX algorithms (`rx/loki`, `rx/wow`).
+* **`-DWITH_ARGON2=OFF`** disable Argon2 algorithms (`argon2/chukwa`, `argon2/wrkz`).
+
+## Features
+
+* **`-DWITH_HWLOC=OFF`**
+disable [hwloc](https://github.com/xmrig/xmrig/issues/1077) support.
+Disabling this feature is not recommended in most cases.
+This feature add external dependency to libhwloc (1.10.0+) (except MSVC builds).
+* **`-DWITH_LIBCPUID=OFF`** disable built in libcpuid support, this feature always disabled if hwloc enabled, if both hwloc and libcpuid disabled auto configuration for CPU will very limited.
+* **`-DWITH_HTTP=OFF`** disable built in HTTP support, this feature used for HTTP API and daemon (solo mining) support.
+* **`-DWITH_TLS=OFF`** disable SSL/TLS support (secure connections to pool). This feature add external dependency to OpenSSL.
+* **`-DWITH_ASM=OFF`** disable assembly optimizations for modern CryptoNight algorithms.
+* **`-DWITH_EMBEDDED_CONFIG=ON`** Enable [embedded](https://github.com/xmrig/xmrig/issues/957) config support.
+* **`-DWITH_OPENCL=OFF`** Disable OpenCL backend.
+* **`-DWITH_CUDA=OFF`** Disable CUDA backend.
+* **`-DWITH_SSE4_1=OFF`** Disable SSE 4.1 for Blake2 (useful for arm builds).
+
+## Debug options
+
+* **`-DWITH_DEBUG_LOG=ON`** enable debug log (mostly network requests).
+* **`-DHWLOC_DEBUG=ON`** enable some debug log for hwloc.
+* **`-DCMAKE_BUILD_TYPE=Debug`** enable debug build, only useful for investigate crashes, this option slow down miner.
+
+## Special build options
+
+* **`-DXMRIG_DEPS=<path>`** path to precompiled dependencies https://github.com/xmrig/xmrig-deps
+* **`-DARM_TARGET=<number>`** override ARM target, possible values `7` (ARMv7) and `8` (ARMv8).
+* **`-DUV_INCLUDE_DIR=<path>`** custom path to libuv headers.
+* **`-DUV_LIBRARY=<path>`** custom path to libuv library.
+* **`-DHWLOC_INCLUDE_DIR=<path>`** custom path to hwloc headers.
+* **`-DHWLOC_LIBRARY=<path>`** custom path to hwloc library.
+* **`-DOPENSSL_ROOT_DIR=<path>`** custom path to OpenSSL.