chore: gitignore fetched data files (#178)

These JSON files are regenerated at build time by the fetch scripts,
so they don't need to be tracked in version control.

Co-authored-by: Kaan Karaoglu <9263013+kaankaraoglu@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: kaankaraoglu

.gitignore

@@ -3,6 +3,11 @@ node_modules
 /dist
 
 
+# Fetched data (regenerated at build time)
+src/data/wcl-progression.json
+src/data/wcl-stats.json
+src/data/rio-mythicplus.json
+
 # local env files
 .env
 .env.local