Add Unix system console header and visuals guide documentation

- Created a new header file `unix_syscon.h` for Unix system console functions, including console creation, destruction, and event handling.
- Added a comprehensive `VISUALS.md` guide detailing player highlighting features, color customization, outline thickness, and legacy name changes for the FnQuake3 engine.

Author: themuffinator

LICENSE

@@ -280,7 +280,7 @@ ifeq ($(USE_SYSTEM_VORBIS),1)
 endif
 
 # extract version info
-VERSION=$(shell sed -n 's/^[[:space:]]*#define[[:space:]]*FNQ3_VERSION_STRING[[:space:]]*"\([^"]*\)".*/\1/p' $(VERSION_HEADER))
+VERSION=$(shell awk -F'"' '/^[[:space:]]*#define[[:space:]][[:space:]]*FNQ3_VERSION_STRING[[:space:]][[:space:]]*"/ { print $$2; exit }' $(VERSION_HEADER))
 
 # common qvm definition
 ifeq ($(ARCH),x86_64)
@@ -332,6 +332,7 @@ endif
 
 ifeq ($(USE_SDL),1)
   BASE_CFLAGS += -DSDL_FUNCTION_POINTER_IS_VOID_POINTER=1
+  BASE_CFLAGS += -DUSE_SDL_SYSCON=1
 endif
 
 ifeq ($(USE_CURL),1)
@@ -1246,6 +1247,7 @@ endif # !USE_SDL
 else # !MINGW
 
   Q3OBJ += \
+    $(B)/client/unix_syscon.o \
     $(B)/client/unix_main.o \
     $(B)/client/unix_shared.o \
     $(B)/client/linux_signals.o
@@ -1377,6 +1379,7 @@ ifdef MINGW
 else
   Q3DOBJ += \
   $(B)/ded/linux_signals.o \
+  $(B)/ded/unix_syscon.o \
   $(B)/ded/unix_main.o \
   $(B)/ded/unix_shared.o
 endif

Makefile

@@ -23,6 +23,7 @@ FnQuake3 is a modernized Quake III Arena engine project built around a simple go
 
 ## Features
 
+- Optional player highlighting with rimlight and stencil border effects, per-mode team or free colors, and teammate/enemy override colors. See the [Visuals guide](docs/VISUALS.md).
 - Flexible 4:3-aware aspect correction for HUDs, menus, UI model widgets, and cinematics, with sensible widescreen options when you want them. See the [Aspect Correction guide](docs/ASPECT_CORRECTION.md).
 - A much more capable console, including configurable scaling, smoother scrolling, mouse interaction, text selection, drag and drop, and an optional live tab-completion popup. See the [Console guide](docs/CONSOLE.md).
 - CPMA/CNQ3-style rainbow text color escapes, with live preview right in the console input line.
@@ -49,6 +50,7 @@ FnQuake3 is a modernized Quake III Arena engine project built around a simple go
 ## Documentation
 
 - [Build Guide](BUILD.md) if you want to compile FnQuake3 yourself.
+- [Visuals Guide](docs/VISUALS.md) for player highlighting and the current visual presentation controls.
 - [Aspect Correction Guide](docs/ASPECT_CORRECTION.md) for HUD, menu, and cinematic presentation options.
 - [Console Guide](docs/CONSOLE.md) for console scaling, interaction, completion, and appearance.
 - [Technical Notes](docs/TECHNICAL.md) for maintainers, release flow, and repo conventions.