docs: add README, LICENSE, .env.example

README in German with universal framing (class, study group, cohort)
rather than INFO1-specific wording. MIT license. Update package.json
with description, keywords, repository URL, proper license field,
start script. Add .env.example documenting required environment
variables.

package.json

@@ -1,14 +1,18 @@
 {
   "name": "info1",
-  "version": "1.0.0",
+  "version": "0.1.0",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "start": "node index.js"
   },
-  "keywords": [],
-  "author": "",
-  "license": "ISC",
-  "description": "",
+  "keywords": ["dashboard", "education", "class", "self-hosted", "e2ee", "express", "sqlite"],
+  "author": "lulinretrograde",
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/lulinretrograde/ifb-schulapp.git"
+  },
+  "description": "Self-hosted class dashboard: timetable, homework, grades, shared calendar, class chat, and end-to-end encrypted direct messages. Built on Node.js, Express, SQLite, vanilla JS.",
   "dependencies": {
     "bcryptjs": "^3.0.3",
     "better-sqlite3": "^12.9.0",