Rebrand application from 'Beach Litter Mapping Platform' to 'Litter Scouts'

- Updated app name in all source files, documentation, and configuration
- Changed package names in package.json files
- Updated header, titles, and user-facing text
- Modified email templates and notification text
- Updated steering rules and spec documents

server/package.json

@@ -1,7 +1,7 @@
 {
-  "name": "beach-litter-api",
+  "name": "litter-scouts-api",
   "version": "1.0.0",
-  "description": "Backend API for Beach Litter Mapping Platform",
+  "description": "Backend API for Litter Scouts",
   "main": "dist/index.js",
   "scripts": {
     "dev": "tsx watch src/index.ts",