Initial sync: memory, agents, commands, and gitignore

Syncs project memory, custom agents, and commands across machines.
Excludes secrets (settings.json), session state, and runtime files.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,29 @@
+# Secrets and machine-local config
+settings.json
+settings.local.json
+
+# Session/runtime state
+history.jsonl
+sessions/
+debug/
+cache/
+paste-cache/
+shell-snapshots/
+session-env/
+file-history/
+backups/
+downloads/
+tasks/
+plans/
+stats-cache.json
+.last-cleanup
+.DS_Store
+
+# Plugins (installed per-machine)
+plugins/
+
+# Projects: only sync memory/ subdirectories
+projects/**
+!projects/*/
+!projects/*/memory/
+!projects/*/memory/**