CI, refactors, fixes, and features

[T9es]

Summary

This PR consolidates work across the GhostGrid-Addons branch including codebase refactoring, bug fixes, new features, and CI setup.

Changes

CI & Tooling

• CI compile-check workflow (.github/workflows/ci.yml) — validates the mod compiles on every push and pull request using GitHub Actions. Downloads tModLoader 1.4.3-legacy (v2022.09.47.89), wires DLL references, runs dotnet build. Catches compilation errors before merge.
• Disabled old broken workflow (main.yml → main.yml.old) — the previous publish-targeted workflow is disabled but preserved for reference.
• GitHub issue templates (bug report, feature request, config) — structured templates for filing issues.
• Copilot instructions (.github/copilot-instructions.md) — project guidelines for the mod body mask system.

Refactoring

• Consolidated StaticDust and StaticDustNormal families (26 dusts → 4 abstract bases)
• Consolidated 10 Emerald projectile families into abstract base classes
• Extracted helpers: SpawnLocator, DrawGlowSphere, SpawnTeleportBurst, TickPillarList, lookup arrays in FairyGlobalNPC/SariaResources
• Split Saria monoliths into partial class files
• Cleaned dev build artifacts and .vs/ cache files

Bug Fixes

• Psychic field fall physics now matches portal gun behavior
• Texture reuse for psychic field content
• Y-bounce disabled on Psychic, Sparkle, Ring3Dust, Cold dusts (restoring original no-bounce behavior)
• Guarded interactive dialogue against empty ID from GetRandomInteractiveDialogue()

Features

• Charged psychic field attack
• CalmMind buff (new)

Housekeeping

• .editorconfig additions for consistent formatting
• New .gitignore entries