Add ~/.omp config; nvim git-repo external; ya pkg install hook

- dot_omp: agent config/keybindings/mcp/themes/commands + loop defs,
  goals, run-loop.sh; dotstate config.yml symlink materialized; dbs,
  logs, sessions, memories, blobs, caches, .env (secret), and
  managed-skills excluded
- .chezmoiexternal.toml: prdlk/nvim as git-repo external — no
  refreshPeriod + ff-only pull, local checkout wins over remote
- yazi plugins: vendored source copies dropped (target-ignored already);
  package.toml is the manifest, installed via run_onchange ya pkg
  install hook; stale piper/easyjump pins bumped to match live content
- herdr: plugins/github checkout, logs, session.json, .bak,
  release-notes dropped from sync (herdr-managed machine state)

dot_omp/private_agent/private_mcp.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "https://raw.githubusercontent.com/can1357/oh-my-pi/main/packages/coding-agent/src/config/mcp-schema.json",
+  "mcpServers": {
+    "exa": {
+      "type": "http",
+      "url": "https://mcp.exa.ai/mcp"
+    }
+  }
+}