Style: Partially apply clang-tidy's `cppcoreguidelines-pro-type-member-init`

Didn't commit all the changes where it wants to initialize a struct
with `{}`. Should be reviewed in a separate PR.

Option `IgnoreArrays` enabled for now to be conservative, can be
disabled to see if it proposes more useful changes.

Also fixed manually a handful of other missing initializations / moved
some from constructors.

1 files changed, 1 insertions, 1 deletions

diff --git a/scene/2d/area_2d.h b/scene/2d/area_2d.h
index 68047ccebf..a42e7722b0 100644
--- a/scene/2d/area_2d.h
+++ b/scene/2d/area_2d.h
@@ -49,7 +49,7 @@ public:
 private:
 	SpaceOverride gravity_space_override = SPACE_OVERRIDE_DISABLED;
 	Vector2 gravity_vec;
-	real_t gravity;
+	real_t gravity = 0.0;
 	bool gravity_is_point = false;
 	real_t gravity_distance_scale = 0.0;