Add db-forest-config.xml to JetBrains gitignore

- It stores the IntelliJ Database tool window tree state (which data source  nodes are expanded, and in what order) — per-developer UI state that churns on  every expand/collapse, exactly like the already-ignored workspace.xml.
- Its payload tracks developer's local-only  connections, so committing the file might push dangling references into every teammate's IDE.

Global/JetBrains.gitignore

@@ -3,6 +3,7 @@
 
 # User-specific stuff
 .idea/**/workspace.xml
+.idea/**/db-forest-config.xml
 .idea/**/tasks.xml
 .idea/**/usage.statistics.xml
 .idea/**/dictionaries