chore: gitignore .claude/ and .remember/

Workspace flatten brought these operator-scoped state dirs (Claude
Code per-machine settings and remember-skill memory artifacts) into
the repo's working tree. Neither belongs in git — the canonical
project memory lives under ~/.claude/projects/ outside the repo.

.gitignore

@@ -33,6 +33,12 @@ go.work.sum
 # canonical record lives in commit messages and the running code).
 docs/superpowers/
 
+# Per-machine Claude Code settings + remember-skill memory artifacts.
+# Both are operator-scoped; the canonical project memory lives under
+# ~/.claude/projects/ outside the repo.
+.claude/
+.remember/
+
 # Flutter
 flutter_client/.dart_tool/
 flutter_client/.flutter-plugins