chore: clean up repo for public release

- Remove BMAD framework, IDE configs, dev screenshots, test files,
  internal docs, and backup files
- Rename keep-notes/ to memento-note/
- Update all references from keep-notes to memento-note
- Add Apache 2.0 license with Commons Clause (non-commercial restriction)
- Add clean .gitignore and .env.docker.example

mcp-server/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "memento-mcp-server",
-  "version": "3.0.0",
+  "version": "3.1.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "memento-mcp-server",
-      "version": "3.0.0",
+      "version": "3.1.0",
       "dependencies": {
         "@modelcontextprotocol/sdk": "^1.0.4",
         "@prisma/client": "^5.22.0",
@@ -17,6 +17,9 @@
       "devDependencies": {
         "@types/node": "^20.0.0",
         "prisma": "^5.22.0"
+      },
+      "engines": {
+        "node": ">=18.0.0"
       }
     },
     "node_modules/@hono/node-server": {