Remove macOS Intel build — free tier runners unavailable

macos-12 and macos-13 Intel runners are no longer available on GitHub
free tier (stuck waiting 12+ hours). macOS arm64 covers M1/M2/M3/M4
(~95% of current Mac users). Intel users can run from source.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: 2 people

.github/workflows/build.yml

@@ -19,10 +19,6 @@ jobs:
             platform: macos-arm64
             artifact: GCodeZAA-macos-arm64.dmg
 
-          - os: macos-12
-            platform: macos-x64
-            artifact: GCodeZAA-macos-x64.dmg
-
           - os: windows-latest
             platform: windows-x64
             artifact: GCodeZAA-windows-x64-Setup.exe
@@ -165,7 +161,6 @@ jobs:
             | Platforma | Soubor | Poznámka |
             |-----------|--------|----------|
             | macOS Apple Silicon (M1/M2/M3/M4) | `GCodeZAA-macos-arm64.dmg` | |
-            | macOS Intel | `GCodeZAA-macos-x64.dmg` | |
             | Windows 10/11 x64 | `GCodeZAA-windows-x64-Setup.exe` | Spusť installer, vytvoří zástupce |
             | Linux x86_64 | `GCodeZAA-linux-x64.AppImage` | `chmod +x`, pak spusť |
             | Linux ARM64 (Raspberry Pi 4/5) | `GCodeZAA-linux-arm64.AppImage` | GUI funkční, ZAA bez open3d¹ |