meson: copy automation files to build directory

This enables running Moonscript on Windows builds without relying on system files

automation/include/aegisub/meson.build

@@ -0,0 +1,14 @@
+# Copy files to build directory for testing purposes
+lua_files = files(
+    'argcheck.moon',
+    'clipboard.lua',
+    'ffi.moon',
+    'lfs.moon',
+    're.moon',
+    'unicode.moon',
+    'util.moon',
+)
+
+foreach f: lua_files
+    configure_file(input: f, output: '@PLAINNAME@', copy: true)
+endforeach

automation/include/meson.build

@@ -0,0 +1,19 @@
+# Copy files to build directory for testing purposes
+lua_files = files(
+    'cleantags.lua',
+    'clipboard.lua',
+    'karaskel-auto4.lua',
+    'karaskel.lua',
+    'lfs.lua',
+    'moonscript.lua',
+    're.lua',
+    'unicode.lua',
+    'utils-auto4.lua',
+    'utils.lua',
+)
+
+foreach f: lua_files
+    configure_file(input: f, output: '@PLAINNAME@', copy: true)
+endforeach
+
+subdir('aegisub')

automation/meson.build

@@ -1,3 +1,5 @@
+subdir('include')
+
 automation_dir = dataroot / 'automation'
 
 install_data(