release: v4.0.0 — ecosystem integration (marketplace, interop, skill API)

- Add marketplace metadata to both plugin manifests (author, license, category, tags)
- Declare lossless-claw complementary positioning via interop field
- Expose mc:recall as programmatic service (api.exposeService)
- Fix CJK hashtag regex to support Unicode property escapes
- Create MARKETPLACE.md for marketplace listing
- Update README with marketplace install, interop docs, and API docs

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

mc-plugin/openclaw.plugin.json

@@ -2,7 +2,13 @@
   "id": "mc",
   "name": "Memory Continuity Commands",
   "description": "Slash commands for Memory Continuity — /mc state, /mc history, /mc search, /mc settings, etc.",
-  "version": "1.0.0",
+  "version": "2.0.0",
+  "author": { "name": "dtzp555-max", "url": "https://github.com/dtzp555-max" },
+  "license": "MIT",
+  "category": "commands",
+  "tags": ["memory", "commands", "search", "recall"],
+  "icon": "terminal",
+  "requires": ["memory-continuity"],
   "configSchema": {
     "type": "object",
     "additionalProperties": false,