Add open-config script, VS Code tasks, and vanilla file warnings

.kilo/agent/lyndas_mod.md

@@ -121,8 +121,30 @@ The following v3 mods are available in the mod launcher (under `C:\7D2D\v3\`):
 When Lynda wants to review game config files:
 - Run VS Code task `Open 7D2D Game Config Folder` (`Ctrl+Shift+B`) to open `C:\Steam\steamapps\common\7 Days To Die\Data\Config` in Explorer
 - Run VS Code task `Open 7D2D Steam Mods Folder` (`Ctrl+Shift+B`) to open the Steam `Mods` folder in Explorer
+- Run `.kilo/scripts/open-config.ps1 -Filename "archetypes.xml"` to open a specific config file in VS Code
 - Or run `.kilo/scripts/open-game-config.ps1` / `.kilo/scripts/open-mods-folder.ps1`
 
+## ⚠️ CRITICAL: Do Not Edit Vanilla Game Files Directly!
+
+**Never edit files in `C:\Steam\steamapps\common\7 Days To Die\Data\Config\` or other game directories directly!**
+
+These are the game's base files. Editing them directly will:
+- **Be overwritten** when the game updates via Steam
+- **Not be tracked** by git
+- **Break mod compatibility** when switching between modded and vanilla play
+- **Require manual reverting** if you want to restore original settings
+
+### Correct Workflow
+
+1. **Review** vanilla config files using `open-config.ps1` to find the settings you want to change
+2. **Note the XPath** or exact values you want to modify
+3. **Create a modlet** in `mods/` that overrides those values using XPath
+4. **Enable/sync** the modlet to test
+5. **Disable** the modlet when done testing
+6. **Commit** the modlet to git
+
+When helping Lynda, always guide her toward creating a modlet rather than editing the base game files.
+
 ## Finding What to Change
 
 When Lynda wants to make a specific change but doesn't know which file to edit, use `CONFIG-REFERENCE.md` to identify the relevant XML config file. Common entry points: