Write header files

I need a header for the physics component used across our game engine. Put class declarations, public API comments, include guards, and forward declarations only. Name the file PhysicsComponent.h, expose methods Init, Update(float dt), ApplyForce(const Vector3&), and Serialize(Serializer&). Keep implementation out; ensure dependencies are declared but not included. Ladder":"L1"

Before I commit PhysicsComponent.h to the repo, make it easy for other engineers to read and use. Move the most-used methods to the top, add a one-paragraph summary of responsibilities, clearly mark which functions are thread-safe, and call out any dependencies that require specific build flags. Show where to add inline helpers later. Ladder":"L2"

I pulled out all method bodies into PhysicsComponent.cpp; other teams report compile errors in AI and Networking about unresolved types and missing symbols. The build logs point to missing includes and forward declarations but I’m not sure which headers to publish in the header versus hide in the cpp. I’m worried exposing too many headers will increase coupling. What's the likely cause and the best next change to the header to fix the build without leaking implementation details? Ladder":"L5"

Across projects I keep adding includes to headers and our incremental builds and merges slow. My patches repeatedly get blobs of unrelated includes because I’m trying to fix compile errors quickly. What habit should I change so headers stay thin, builds stay fast, and other engineers stop pinging me to fix transitive include breaks? Recommend a concrete checklist and a code review checklist to enforce it. Ladder":"L6"