feat: BIND DNS Web Manager - Web interface for managing BIND9 DNS server

- Flask + SQLite web app with user authentication
- Zone management: create/delete zones, edit raw zone files
- Record management: add/delete A/AAAA/CNAME/MX/TXT/NS/PTR/SRV/CAA records
- Service control: start/stop/restart/reload BIND via systemctl/rndc
- Configuration editor: edit named.conf.options/local with syntax validation
- DNS query testing: online dig tool
- Audit log: all operations logged with user/timestamp
- BIND9 backend, listening on port 53

templates/zone_form.html

@@ -0,0 +1,45 @@
+{% extends "base.html" %}
+{% block title %}{% if zone %}编辑域名{% else %}创建域名{% endif %} - DNS{% endblock %}
+{% block content %}
+<div class="page-header">
+    <h1>{% if zone %}编辑域名{% else %}创建域名{% endif %}</h1>
+</div>
+
+<div class="card">
+    <div class="card-body">
+        <form method="POST" class="form">
+            <div class="form-group">
+                <label>域名 <span class="required">*</span></label>
+                <input type="text" name="zone_name" placeholder="example.com" required
+                       value="{{ zone.name if zone else '' }}">
+                <p class="form-hint">不含末尾的点，例如 example.com</p>
+            </div>
+
+            <div class="form-group">
+                <label>类型</label>
+                <select name="zone_type">
+                    <option value="master" selected>master (主域)</option>
+                    <option value="slave">slave (从域)</option>
+                </select>
+            </div>
+
+            <div class="form-group">
+                <label>主 NS 服务器</label>
+                <input type="text" name="ns_server" placeholder="ns1.example.com">
+                <p class="form-hint">留空则自动使用 ns1.<域名></p>
+            </div>
+
+            <div class="form-group">
+                <label>管理员邮箱</label>
+                <input type="text" name="admin_email" placeholder="admin@example.com">
+                <p class="form-hint">留空则自动使用 admin.<域名>，会自动将 @ 转为 .</p>
+            </div>
+
+            <div class="form-actions">
+                <button type="submit" class="btn btn-primary">创建域名</button>
+                <a href="{{ url_for('zone_list') }}" class="btn btn-secondary">取消</a>
+            </div>
+        </form>
+    </div>
+</div>
+{% endblock %}