chore: gitignore *.local files at project level + strip phase residuals

Previously .claude/settings.local.json was only excluded by the user's
global ~/.config/git/ignore — fresh clones of this template would have
accidentally committed per-user Claude Code settings. Add an explicit
project-level rule (*.local, *.local.*, **/settings.local.json) so the
template ships with the protection baked in.

Also strips two missed "phase" residuals from
core-shared/instrumentation/otel/init-server-node.ts (the word leaked
through the earlier sweep — generic future-work qualifier, not a
setup-history reference, but cleaner without it).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -16,6 +16,11 @@ storybook-static
 .env.local
 .env.*.local
 
+# Per-user local overrides (never commit — .claude/settings.local.json, etc.)
+*.local
+*.local.*
+**/settings.local.json
+
 # Testing
 coverage