Source2Gen is an executable + Linux support

[Cre3per]

PR #47

My dear ladies, I bring sunshine! (And a large pull request, sorry for that)

dll -> exe

The goal of this issue is to convert source2gen from an injected library to an executable. This brings several benefits

• Ease of use, no need for an injector
• Works on headless systems (Servers), because the game does't need to be running
• No more waiting for the game to be ready, we make it ready!
  • It's fast, about 2 seconds to dump CS2, start to finish
    • makes debugging a bliss
• Single-threaded
• No manually-created console

How does it work?

• Load all libraries that we intend to dump
• Call InstallSchemaBindings() in each of those libraries
• Dump as per usual

Linux Support

This is what makes the issue a little bigger. I don't have Windows, and I can't run games, so I had to make both changes at once.

How does it work?

• Add some macros to make conditional code easier (tools/platform.h)
• Add a cross-platform module loader that uses libloaderapi on Windows and dlfcn on Linux (tools/loader.h)
• Update structs and assertions to match offsets in Linux games
• Make the code compatible with more compilers (clang++, g++)
  • Fix case-sensitive file and entity names
  • Add missing includes
  • NOP mscv macros on Linux
  • Some other minor changes

Status

This is where this issue still needs help. As I don't have Windows and there is no CI, I can't make sure I'm not breaking anything. I wrote all code with Windows in mind, it should still work, but I can't test it.

• ✔️ Runs and dumps on linux
• 🚫 Generated SDK tested on Linux - Postponed, merge in alpha quality with disclaimer in readme to avoid diverging from master
• ❌ Compiles on Windows
  • ❌ Update premake to build an executable instead of a library
  • ❌ Fix loader_windows.h if necessary
  • ❌ Fix compiler bugs that were added in the linux port, if necessary
• ❌ Runs on Windows without crashing
• ❌ Dumps on Windows, with no regressions
• ❌ Documentation about how to run source2gen on Windows (Need to set PATH to load libraries) (Hint: Perhaps we can use the registry to find the game path and set PATH automatically)