Battle formulas: action values as stat formulas, costs from stat pools, MP gauge for party members, action schema

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitignore

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+# Godot 4.x
+.godot/
+.idea/
+sdk/
+bin/
+obj/
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+#ai
+.omo/
+.opencode/
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+gen/
+obj/
+bin/
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+*.tres~
+*.tscn~
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+# GDScript LSP
+.godot/
+
+# Export
+*.exe
+*.dmg
+*.apk
+*.aab
+*.pck
+*.zip
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+# OS
+.DS_Store
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+*.import
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