[Build] Add an ENABLE_SANITIZERS option for ASan and UBSan

Adds -DENABLE_SANITIZERS, off by default, building with AddressSanitizer and
UndefinedBehaviorSanitizer. The bulk of the work is in the three ways the obvious
implementation silently does the wrong thing.

Probe the flags on the link step, not just the compile step. check_cxx_compiler_flag()
only compiles, so every sanitizer flag comes back unsupported, because linking an ASan
object without -fsanitize=address leaves __asan_init undefined. The result is not a
build failure but a build that appears instrumented and is not, which is worse. Use
check_cxx_source_compiles() with CMAKE_REQUIRED_LINK_OPTIONS instead, and treat an
unsupported sanitizer pair as fatal since the cosmetic flags are allowed to degrade.

Opt vendored sources out per source, through a cockatrice_disable_sanitizers_for()
helper rather than a list of set_source_files_properties() calls at the root. The
helper has to exist because CMake resolves a source-file property against the directory
scope its target was declared in: setting the property from the root with absolute paths
is a no-op, silently, which is why the call sites sit next to the add_library and
add_executable that pull the vendored code in. SFMT, minizip, the LZMA SDK and Qxt SMTP
are excluded. oracle/src/qt-json is in the history but not in the tree, removed in
#7214.

Also mark those sources SKIP_PRECOMPILE_HEADERS. The PCH is built with the sanitizer
flags, so it defines __SANITIZE_ADDRESS__; a translation unit compiled with
-fno-sanitize=all does not and GCC then refuses the PCH, which is a fatal
-Werror=invalid-pch in the servatrice and oracle builds.

-fno-sanitize=vptr is not optional. Qt constructs QObject subclasses into raw storage
and writes the vptr afterwards, so the vptr check reports on essentially every QObject
instantiation, and it has no value here because nothing outside moc-generated code
inherits QObject.

Verified on the resulting build: our own translation units carry ASan and UBSan calls,
SFMT.o carries neither, and the full suite of 464 cases passes clean under
ASAN_OPTIONS=detect_leaks=0:abort_on_error=1 with UBSAN_OPTIONS=halt_on_error=0.

The test suite needs two adjustments to make this option usable at all, both of which
land here because they are consequences of COCKATRICE_SANITIZERS existing rather than
independent changes.

DISCOVERY_TIMEOUT rises from 60s to 300s under sanitizers. An instrumented binary takes
2.8s to answer --gtest_list_tests against 0.04s uninstrumented, and discovery runs
several binaries at once behind a -j build.

One target is excluded via a NO_SANITIZE flag, server_developer_role_test. Reaching
google::protobuf::TextFormat::Printer's destructor aborts on an absl assertion inside
system protobuf 33.4 whenever the consumer translation unit is built without NDEBUG,
which a Debug sanitizer build is. This reproduces with no Cockatrice code at all, just
"TextFormat::Printer p; p.PrintToString(msg, &out);" built with -fsanitize=address, so it
is upstream rather than ours. It is a flag and not a fourth label because "skip this in
the sanitizer leg" has to compose with a test's group rather than compete for the single
label slot, and because a flag excludes by not registering the cases at all, which
cannot rot the way a label silently can. The target still builds and still runs on the
legs without sanitizers.

tests/oracle/CMakeLists.txt

@@ -25,6 +25,7 @@ find_package(ZLIB)
 if(ZLIB_FOUND)
   add_definitions("-DHAS_ZLIB")
   set(_ORACLE_BENCH_EXTRA_SOURCES ../../oracle/src/zip/unzip.cpp ../../oracle/src/zip/zipglobal.cpp)
+  cockatrice_disable_sanitizers_for(${_ORACLE_BENCH_EXTRA_SOURCES})
   set(_ORACLE_BENCH_EXTRA_LIBRARIES ${ZLIB_LIBRARIES})
   include_directories(${ZLIB_INCLUDE_DIRS})
 else()
@@ -35,6 +36,7 @@ find_package(LibLZMA)
 if(LIBLZMA_FOUND)
   add_definitions("-DHAS_LZMA")
   list(APPEND _ORACLE_BENCH_EXTRA_SOURCES ../../oracle/src/lzma/decompress.cpp)
+  cockatrice_disable_sanitizers_for(../../oracle/src/lzma/decompress.cpp)
   list(APPEND _ORACLE_BENCH_EXTRA_LIBRARIES ${LIBLZMA_LIBRARIES})
   include_directories(${LIBLZMA_INCLUDE_DIRS})
 else()