Improve crash handler message display

[Calinou]

Can be merged independently of #33505.

• State the Godot version and full hash in the backtrace.
  • Knowing the exact hash is important because source code backtraces depend on the source code version to be accurate.
• Add decoration around the crash backtrace, both to make it stand out from other messages and help the user figure out what they should copy.

I got the idea to implement this while looking at the comments here: #47732 (comment)

Preview

Before

ERROR: Testing crash handler with CRASH_NOW_MSG
   at: ProjectManager (editor/project_manager.cpp:2379)
handle_crash: Program crashed with signal 4
Dumping the backtrace. Please include this when reporting the bug on https://github.com/godotengine/godot/issues
[1] /lib64/libc.so.6(+0x3da60) [0x7fa094eeaa60] (??:0)
[2] ProjectManager::ProjectManager() (/home/hugo/Documents/Git/godotengine/godot/editor/project_manager.cpp:2379)
[3] Main::start() (/home/hugo/Documents/Git/godotengine/godot/main/main.cpp:2363)
[4] bin/godot.linuxbsd.tools.64.llvm(main+0x1b2) [0x4765822] (/home/hugo/Documents/Git/godotengine/godot/platform/linuxbsd/godot_linuxbsd.cpp:57)
[5] /lib64/libc.so.6(__libc_start_main+0xf2) [0x7fa094ed51e2] (??:0)
[6] bin/godot.linuxbsd.tools.64.llvm(_start+0x2e) [0x47655ae] (??:?)
-- END OF BACKTRACE --
[1]    100306 IOT instruction (core dumped)  bin/godot.linuxbsd.tools.64.llvm

After

ERROR: Testing crash handler with CRASH_NOW_MSG
   at: ProjectManager (editor/project_manager.cpp:2379)

================================================================
handle_crash: Program crashed with signal 4
Engine version: Godot Engine v4.0.dev.custom_build (4e8b67a0d186e39a8e64366ac05a2d6a3df0c2ff)
Dumping the backtrace. Please include this when reporting the bug on https://github.com/godotengine/godot/issues
[1] /lib64/libc.so.6(+0x3da60) [0x7f30fc2e7a60] (??:0)
[2] ProjectManager::ProjectManager() (/home/hugo/Documents/Git/godotengine/godot/editor/project_manager.cpp:2379)
[3] Main::start() (/home/hugo/Documents/Git/godotengine/godot/main/main.cpp:2363)
[4] bin/godot.linuxbsd.tools.64.llvm(main+0x1b2) [0x4765822] (/home/hugo/Documents/Git/godotengine/godot/platform/linuxbsd/godot_linuxbsd.cpp:57)
[5] /lib64/libc.so.6(__libc_start_main+0xf2) [0x7f30fc2d21e2] (??:0)
[6] bin/godot.linuxbsd.tools.64.llvm(_start+0x2e) [0x47655ae] (??:?)
-- END OF BACKTRACE --
================================================================
[1]    95589 IOT instruction (core dumped)  bin/godot.linuxbsd.tools.64.llvm

[akien-mga]

Cherry-picked for 3.4.