feat: 完成 M2 mosh（LAN + tsnet 端到端验证）

- mosh(blinksh/ios C++)+protobuf-lite 交叉编译为 MoshCore.xcframework
  （CommonCrypto 后端、含 arm64 模拟器 slice；绕 autotools 用 CMake 直编 + 手写 config.h）
- tsnet 桥新增 UDP relay（StartMoshRelay：loopback↔tsnet.Dial 逐包搬运）
- MoshSession（pipe↔FILE*/pthread/SIGWINCH）+ MoshConnectScanner（TXCore，+4 单测=39）
- SSHTerminalModel 编排：SSH 引导 mosh-server→解析 MOSH CONNECT→relay→mosh 接管
- LAN 直连 + mosh-over-tsnet 均端到端验证通过，R1(tsnet UDP 数据报语义) 证伪

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vendor/protobuf/third_party/zlib.BUILD

@@ -0,0 +1,69 @@
+load("@rules_cc//cc:defs.bzl", "cc_library")
+
+licenses(["notice"])  # BSD/MIT-like license (for zlib)
+
+exports_files(["zlib.BUILD"])
+
+_ZLIB_HEADERS = [
+    "crc32.h",
+    "deflate.h",
+    "gzguts.h",
+    "inffast.h",
+    "inffixed.h",
+    "inflate.h",
+    "inftrees.h",
+    "trees.h",
+    "zconf.h",
+    "zlib.h",
+    "zutil.h",
+]
+
+_ZLIB_PREFIXED_HEADERS = ["zlib/include/" + hdr for hdr in _ZLIB_HEADERS]
+
+# In order to limit the damage from the `includes` propagation
+# via `:zlib`, copy the public headers to a subdirectory and
+# expose those.
+genrule(
+    name = "copy_public_headers",
+    srcs = _ZLIB_HEADERS,
+    outs = _ZLIB_PREFIXED_HEADERS,
+    cmd_bash = "cp $(SRCS) $(@D)/zlib/include/",
+    cmd_bat = " && ".join(
+        ["@copy /Y $(location %s) $(@D)\\zlib\\include\\  >NUL" %
+         s for s in _ZLIB_HEADERS],
+    ),
+)
+
+cc_library(
+    name = "zlib",
+    srcs = [
+        "adler32.c",
+        "compress.c",
+        "crc32.c",
+        "deflate.c",
+        "gzclose.c",
+        "gzlib.c",
+        "gzread.c",
+        "gzwrite.c",
+        "infback.c",
+        "inffast.c",
+        "inflate.c",
+        "inftrees.c",
+        "trees.c",
+        "uncompr.c",
+        "zutil.c",
+        # Include the un-prefixed headers in srcs to work
+        # around the fact that zlib isn't consistent in its
+        # choice of <> or "" delimiter when including itself.
+    ] + _ZLIB_HEADERS,
+    hdrs = _ZLIB_PREFIXED_HEADERS,
+    copts = select({
+        "@bazel_tools//src/conditions:windows": [],
+        "//conditions:default": [
+            "-Wno-unused-variable",
+            "-Wno-implicit-function-declaration",
+        ],
+    }),
+    includes = ["zlib/include/"],
+    visibility = ["//visibility:public"],
+)