chore: stop this branch touching the root gitignore

Two unrelated edits had crept in. The added `.claude/` line duplicates
`/.claude`, which the same file has already carried since well before this
branch, so it never changed behaviour. Removing the root `.env.*` rule did
change behaviour: contributors lost repo-level cover for any env file
outside docker/telemetry, and the local ignore that masks this on one
machine is not part of the repo.

Restore the rule and drop the duplicate, which leaves the root gitignore
byte-identical to the parent branch.

The scoped rules added under docker/telemetry stay: they keep the three
tracked .env.*.example files visible and stop the generated Grafana Cloud
dashboards being committed, which is telemetry work this branch owns.

.gitignore

@@ -89,4 +89,6 @@ target/
 
 # clangd cache
 /.cache
-.claude/
+
+# Env. file carrying environmental setup data for local or cloud runs.
+.env.*