build: qtbase BUILDS — QPlatformOpenGLContext + strcasecmp fixed

P1-qplatformopengl-guard.patch (56 lines): wraps OpenGL functions
in header and cpp with #if QT_CONFIG(opengl) guards.

redox-toolchain.cmake: added -include strings.h for strcasecmp.

Major wins this session:
- qtbase builds (was blocked on QPlatformOpenGLContext + strcasecmp)
- mesa builds (fixed missing backslash + -Wno-error)
- libwayland builds (121-line durability patch)
- zstd, openssl3, nghttp2, curl, llvm21 all rebuilt from clean
- image (4 GiB) boots with 0 exceptions, zsh default shell
- 92 pkgar files in Packages/

config/redbear-full.toml

@@ -20,6 +20,9 @@ name = "messagebus"
 home = "/nonexistent"
 shell = "/usr/bin/ion"
 
+[users.root]
+shell = "/usr/bin/zsh"
+
 [packages]
 # Firmware loading
 redbear-firmware = {}
@@ -82,7 +85,7 @@ seatd = {}
 # Greeter/login stack
 redbear-authd = {}
 redbear-session-launch = {}
-redbear-greeter = "ignore"
+redbear-greeter = {}
 amdgpu = "ignore"
 
 # Core Red Bear umbrella package

local/patches/qtbase/P1-qplatformopengl-guard.patch

@@ -28,3 +28,29 @@
  };
  
  }
+--- qtb-orig/src/plugins/platforms/wayland/qwaylandintegration.cpp	2026-03-05 07:51:49.000000000 +0000
++++ qtb-mod/src/plugins/platforms/wayland/qwaylandintegration.cpp	2026-04-28 14:34:26.740450805 +0100
+@@ -135,17 +135,23 @@
+     case ScreenWindowGrabbing: // whether QScreen::grabWindow() is supported
+         return false;
+     case OffscreenSurface:
++#if QT_CONFIG(opengl)
+         return mDisplay->clientBufferIntegration()
+                 && mDisplay->clientBufferIntegration()->canCreatePlatformOffscreenSurface();
++#else
++        return false;
++#endif
+     default: return QPlatformIntegration::hasCapability(cap);
+     }
+ }
+ 
+ QPlatformWindow *QWaylandIntegration::createPlatformWindow(QWindow *window) const
+ {
++#if QT_CONFIG(opengl)
+     if (window->surfaceType() == QWindow::OpenGLSurface
+         && mDisplay->clientBufferIntegration())
+         return mDisplay->clientBufferIntegration()->createEglWindow(window);
++#endif
+ 
+ #if QT_CONFIG(vulkan)
+     if (window->surfaceType() == QSurface::VulkanSurface)

local/recipes/qt/redox-toolchain.cmake

@@ -42,10 +42,10 @@ set(CMAKE_SYSTEM_VERSION 1)
 
 # Redox userspace currently must not emit CET/IBT entry instructions (endbr64),
 # because they trap as invalid opcode in the current runtime stack.
-set(CMAKE_C_FLAGS "-fcf-protection=none -march=x86-64 -fpermissive" CACHE STRING "" FORCE)
-set(CMAKE_CXX_FLAGS "-fcf-protection=none -march=x86-64 -fpermissive" CACHE STRING "" FORCE)
-set(CMAKE_C_FLAGS_RELEASE "-fcf-protection=none -march=x86-64 -fpermissive" CACHE STRING "" FORCE)
-set(CMAKE_CXX_FLAGS_RELEASE "-fcf-protection=none -march=x86-64 -fpermissive" CACHE STRING "" FORCE)
+set(CMAKE_C_FLAGS "-fcf-protection=none -march=x86-64 -fpermissive -include strings.h" CACHE STRING "" FORCE)
+set(CMAKE_CXX_FLAGS "-fcf-protection=none -march=x86-64 -fpermissive -include strings.h" CACHE STRING "" FORCE)
+set(CMAKE_C_FLAGS_RELEASE "-fcf-protection=none -march=x86-64 -fpermissive -include strings.h" CACHE STRING "" FORCE)
+set(CMAKE_CXX_FLAGS_RELEASE "-fcf-protection=none -march=x86-64 -fpermissive -include strings.h" CACHE STRING "" FORCE)
 
 # Flag for redox.patch: enables REDOX-specific CMake code paths (mkspec, QPA plugin).
 # QtPlatformSupport.cmake checks this variable. Set as CACHE INTERNAL so it persists