chore: stop line-ending churn, track the enabled plugin

Obsidian writes CRLF on Windows, so git reported untouched files as
modified. That matters because `git diff HEAD` is the review surface
after a headless ingest and is useless if everything shows as changed.
`* -text` stores bytes as-is.

.obsidian/community-plugins.json

@@ -0,0 +1,3 @@
+[
+  "webinar-dash"
+]