chore: initial backup of Claude Code configuration

Includes: CLAUDE.md, settings.json, agents, commands, rules, skills,
hooks, contexts, evals, get-shit-done, plugin configs (installed list
and marketplace sources). Excludes credentials, runtime caches,
telemetry, session data, and plugin binary cache.

.gitignore

@@ -0,0 +1,41 @@
+# Secrets
+.credentials.json
+
+# Runtime / cache / machine-specific
+history.jsonl
+sessions/
+cache/
+telemetry/
+projects/
+shell-snapshots/
+file-history/
+backups/
+paste-cache/
+debug/
+metrics/
+statsig/
+homunculus/
+ide/
+plans/
+transcripts/
+tasks/
+session-env/
+todos/
+
+# Machine-specific settings (MCP paths, local permissions)
+settings.local.json
+.claude/settings.local.json
+
+# Cache files
+*-cache.json
+stats-cache.json
+
+# Plugins - only keep config, skip downloaded content
+plugins/cache/
+plugins/marketplaces/
+plugins/repos/
+plugins/data/
+
+# OS files
+.DS_Store
+Thumbs.db