v3.0.0: Add /mc interactive commands for Telegram/Discord/CLI

New companion plugin (mc-plugin/) registers /mc as a native OpenClaw
slash command with 10 subcommands: state, history, restore, clear,
search, settings, compact, export. All commands work across multiple
agent workspaces and return instant responses (direct file reads,
no model invocation).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

mc-plugin/package.json

@@ -0,0 +1,14 @@
+{
+  "name": "mc-plugin",
+  "version": "1.0.0",
+  "description": "Slash commands for Memory Continuity — /mc state, /mc history, /mc search, etc.",
+  "main": "index.js",
+  "type": "module",
+  "keywords": ["openclaw", "plugin", "memory", "continuity"],
+  "license": "MIT",
+  "openclaw": {
+    "type": "plugin",
+    "id": "mc",
+    "pluginManifest": "openclaw.plugin.json"
+  }
+}