fix: add py::mod_gil_used() spelling, support pedantic tests (#5797)

* tests: add linking warnings/error

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* tests: check pedantic C++14

* fix: some pedantic warnings

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* feat: add py::mod_gil_used()

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix: use not_supported()

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* style: pre-commit fixes

* Update CMakeLists.txt

* fix: remove the true/false parameter from mod_gil_not_used

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* style: pre-commit fixes

* Update tests/CMakeLists.txt

* fix: deprecate mod_gil_not_used(bool) instead of removing it

Keep the bool constructor public and mark it deprecated, so existing
code that spells mod_gil_not_used(false) still compiles. mod_gil_used()
now sets the flag through its friendship, which keeps the deprecated
constructor the only bool overload and stops pybind11 warning against
itself.

Also use the py:: alias in exo_planet_pybind11.cpp to match its sibling
home_planet_very_lonely_traveler.cpp.

Assisted-by: ClaudeCode:claude-opus-5

* fix: add trailing comma to macros picked up in rebase

test_smart_ptr.cpp and standalone_enum_module.cpp came from master after
this branch was written, so they still invoked variadic macros with no
variadic argument. That is a pedantic error below C++20.

Assisted-by: ClaudeCode:claude-opus-5

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

tests/test_virtual_functions.cpp

@@ -219,7 +219,7 @@ public:
 };
 
 class test_override_cache_helper_trampoline : public test_override_cache_helper {
-    int func() override { PYBIND11_OVERRIDE(int, test_override_cache_helper, func); }
+    int func() override { PYBIND11_OVERRIDE(int, test_override_cache_helper, func, ); }
 };
 
 inline int test_override_cache(std::shared_ptr<test_override_cache_helper> const &instance) {
@@ -279,7 +279,7 @@ TEST_SUBMODULE(virtual_functions, m) {
             py::print("PyA.f()");
             // This convolution just gives a `void`, but tests that PYBIND11_TYPE() works to
             // protect a type containing a ,
-            PYBIND11_OVERRIDE(PYBIND11_TYPE(typename std::enable_if<true, void>::type), A, f);
+            PYBIND11_OVERRIDE(PYBIND11_TYPE(typename std::enable_if<true, void>::type), A, f, );
         }
     };
 
@@ -302,7 +302,7 @@ TEST_SUBMODULE(virtual_functions, m) {
         ~PyA2() override { py::print("PyA2.~PyA2()"); }
         void f() override {
             py::print("PyA2.f()");
-            PYBIND11_OVERRIDE(void, A2, f);
+            PYBIND11_OVERRIDE(void, A2, f, );
         }
     };
 
@@ -370,26 +370,26 @@ TEST_SUBMODULE(virtual_functions, m) {
     public:
         using OverrideTest::OverrideTest;
         std::string str_value() override {
-            PYBIND11_OVERRIDE(std::string, OverrideTest, str_value);
+            PYBIND11_OVERRIDE(std::string, OverrideTest, str_value, );
         }
         // Not allowed (enabling the below should hit a static_assert failure): we can't get a
         // reference to a python numeric value, since we only copy values in the numeric type
         // caster:
 #ifdef PYBIND11_NEVER_DEFINED_EVER
         std::string &str_ref() override {
-            PYBIND11_OVERRIDE(std::string &, OverrideTest, str_ref);
+            PYBIND11_OVERRIDE(std::string &, OverrideTest, str_ref, );
         }
 #endif
         // But we can work around it like this:
     private:
         std::string _tmp;
-        std::string str_ref_helper() { PYBIND11_OVERRIDE(std::string, OverrideTest, str_ref); }
+        std::string str_ref_helper() { PYBIND11_OVERRIDE(std::string, OverrideTest, str_ref, ); }
 
     public:
         std::string &str_ref() override { return _tmp = str_ref_helper(); }
 
-        A A_value() override { PYBIND11_OVERRIDE(A, OverrideTest, A_value); }
-        A &A_ref() override { PYBIND11_OVERRIDE(A &, OverrideTest, A_ref); }
+        A A_value() override { PYBIND11_OVERRIDE(A, OverrideTest, A_value, ); }
+        A &A_ref() override { PYBIND11_OVERRIDE(A &, OverrideTest, A_ref, ); }
     };
 
     py::class_<OverrideTest::A>(m, "OverrideTest_A")