Initial commit: LMS microservices scaffold

- Gradle multi-module: libs/{common-http,security-jwt,markdown,test-support},
  services/{identity,academic,progress,gateway}, web (Thymeleaf+htmx)
- identity-service: JWT auth (RSA), accounts, students, groups, enrollment,
  import from XLSX/CSV, credentials export, password reset
- academic-service: lab import from JSON/zip (markdown + YAML + variants),
  levels, API
- progress-service: schema for student levels and variant assignments
- gateway: Spring Cloud Gateway, JWT validation, route propagation
- web: Server-side UI with flex/footer layout, light/dark theme toggle,
  admin dashboard, groups CRUD, student portal placeholder
- docker-compose: PostgreSQL 18
- Tests: identity smoke test with Testcontainers

web/src/main/resources/templates/login.html

@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html lang="ru" xmlns:th="http://www.thymeleaf.org"
+      th:replace="~{fragments/base :: layout(~{::title}, ~{::#content})}">
+<head><title>Вход — LMS</title></head>
+<body>
+<div id="content">
+    <div style="max-width:28rem;margin:0 auto;">
+        <h1 style="margin:0 0 1.5rem;font-size:1.5rem;font-weight:600;">Вход</h1>
+
+        <div th:if="${error}" style="margin-bottom:1rem;padding:0.75rem 1rem;border-radius:0.5rem;font-size:0.875rem;background:#fef2f2;color:#991b1b;"
+             th:text="${error}"></div>
+
+        <div th:if="${!adminExists}" style="margin-bottom:1rem;padding:0.75rem 1rem;border-radius:0.5rem;font-size:0.875rem;background:#fef3c7;color:#92400e;">
+            Аккаунт администратора ещё не создан.
+            <a th:href="@{/setup}">Создать первый аккаунт</a>
+        </div>
+
+        <form class="card" style="padding:1.5rem;display:flex;flex-direction:column;gap:1rem;" th:action="@{/login}" method="post">
+            <div>
+                <label class="label" for="login">Логин</label>
+                <input class="input" id="login" name="login" th:value="${login}" autofocus required>
+            </div>
+            <div>
+                <label class="label" for="password">Пароль</label>
+                <input class="input" id="password" name="password" type="password" required>
+            </div>
+            <button class="btn btn-primary" type="submit">Войти</button>
+        </form>
+    </div>
+</div>
+</body>
+</html>