🔧 chore(repo): restructure project file hierarchy

- move project files out of fleetledger directory to root
- update .gitignore to reflect new .env path

📝 docs(README): add detailed project description

- provide an overview of FleetLedger's features and usage
- include setup instructions and security notes

app/templates/register.html

@@ -0,0 +1,62 @@
+{% extends "base.html" %}
+{% block content %}
+<div class="max-w-sm mx-auto mt-8">
+  <h1 class="text-lg font-semibold tracking-tight mb-1">Registrieren</h1>
+  <p class="text-xs text-slate-400 mb-4">
+    Erstelle einen neuen Account. Der erste Benutzer wird automatisch Admin.
+  </p>
+
+  {% if error %}
+  <div class="mb-4 text-xs text-rose-200 bg-rose-500/10 border border-rose-500/60 rounded-lg p-3">
+    {{ error }}
+  </div>
+  {% endif %}
+
+  <form method="post" class="space-y-4">
+    <input type="hidden" name="csrf_token" value="{{ csrf_token }}" />
+    <div class="space-y-1">
+      <label class="text-xs text-slate-300">Benutzername</label>
+      <input
+        type="text"
+        name="username"
+        required
+        class="w-full rounded-lg border border-slate-700 bg-slate-950/60 px-3 py-2 text-sm outline-none focus:border-indigo-500"
+      />
+    </div>
+    <div class="space-y-1">
+      <label class="text-xs text-slate-300">E-Mail (optional)</label>
+      <input
+        type="email"
+        name="email"
+        class="w-full rounded-lg border border-slate-700 bg-slate-950/60 px-3 py-2 text-sm outline-none focus:border-indigo-500"
+      />
+    </div>
+    <div class="space-y-1">
+      <label class="text-xs text-slate-300">Passwort</label>
+      <input
+        type="password"
+        name="password"
+        required
+        minlength="8"
+        class="w-full rounded-lg border border-slate-700 bg-slate-950/60 px-3 py-2 text-sm outline-none focus:border-indigo-500"
+      />
+    </div>
+    <div class="space-y-1">
+      <label class="text-xs text-slate-300">Passwort bestätigen</label>
+      <input
+        type="password"
+        name="password_confirm"
+        required
+        minlength="8"
+        class="w-full rounded-lg border border-slate-700 bg-slate-950/60 px-3 py-2 text-sm outline-none focus:border-indigo-500"
+      />
+    </div>
+    <button
+      type="submit"
+      class="w-full rounded-lg bg-indigo-500 px-4 py-2 text-sm font-medium text-white hover:bg-indigo-400 focus:outline-none focus:ring focus:ring-indigo-500/40"
+    >
+      Account anlegen
+    </button>
+  </form>
+</div>
+{% endblock %}