zed: Reinstate default file_scan_exclusions in Zed repo project settings (#29690)

Closes #ISSUE

Re-adds default `file_scan_exclusions` to [project
settings](84e4891d54/.zed/settings.json)
that were overridden in #29106

Release Notes:

- N/A *or* Added/Fixed/Improved ...

.zed/settings.json

@@ -46,5 +46,17 @@
   "formatter": "auto",
   "remove_trailing_whitespace_on_save": true,
   "ensure_final_newline_on_save": true,
-  "file_scan_exclusions": ["crates/eval/worktrees/", "crates/eval/repos/"]
+  "file_scan_exclusions": [
+    "crates/eval/worktrees/",
+    "crates/eval/repos/",
+    "**/.git",
+    "**/.svn",
+    "**/.hg",
+    "**/.jj",
+    "**/CVS",
+    "**/.DS_Store",
+    "**/Thumbs.db",
+    "**/.classpath",
+    "**/.settings"
+  ]
 }