chore: standardize cross-platform development setup

.gitignore

@@ -1,44 +1,78 @@
-# Godot import cache
-.import/
-
-# Godot editor generated files
+# Godot 4 editor data and imported asset cache
 .godot/
 
-# Export templates and builds
+# Godot 3 imported asset cache
+.import/
+
+# Local export output (keep export_presets.cfg tracked)
 /export/
 /exports/
 /build/
 /builds/
+/dist/
 
-# Mono / C#
+# Godot C# / Mono generated files
 .mono/
 data_*/
 mono_crash.*
-
-# Visual Studio / Rider
-.vs/
-.idea/
 *.csproj
 *.sln
-*.user
-*.DotSettings.user
 
-# macOS
-.DS_Store
-
-# Linux
-.directory
-
-# Windows
-Thumbs.db
-desktop.ini
-
-# Logs
+# Godot and application crash/log output
+crash_handler*
 *.log
 
-# Temporary files
-*.tmp
-*.bak
+# Local environment and secrets
+.env
+.env.*
+!.env.example
 
-# Godot crash reports
-crash_handler*
+# Editors and IDEs
+.idea/
+.fleet/
+.vs/
+.vscode/
+*.code-workspace
+*.suo
+*.user
+*.userosscache
+*.sln.docstates
+*.DotSettings.user
+
+# Editor swap, backup, and temporary files
+*.bak
+*.orig
+*.rej
+*.swp
+*.swo
+*.temp
+*.tmp
+*~
+.#*
+\#*\#
+
+# macOS metadata
+.DS_Store
+.AppleDouble
+.LSOverride
+Icon?
+._*
+.DocumentRevisions-V100/
+.Spotlight-V100/
+.TemporaryItems/
+.Trashes/
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Windows metadata
+Thumbs.db
+Thumbs.db:encryptable
+ehthumbs.db
+ehthumbs_vista.db
+[Dd]esktop.ini
+$RECYCLE.BIN/
+*.stackdump
+
+# Linux desktop and trash metadata
+.directory
+.Trash-*