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/change_password.html

@@ -0,0 +1,31 @@
+{% extends "base.html" %}
+{% block title %}修改密码 - DNS{% endblock %}
+{% block content %}
+<div class="page-header">
+    <h1>修改密码</h1>
+</div>
+
+<div class="card" style="max-width:500px;margin:0 auto">
+    <div class="card-body">
+        <form method="POST" class="form">
+            <div class="form-group">
+                <label>旧密码 <span class="required">*</span></label>
+                <input type="password" name="old_password" required>
+            </div>
+            <div class="form-group">
+                <label>新密码 <span class="required">*</span></label>
+                <input type="password" name="new_password" required minlength="6">
+                <p class="form-hint">至少 6 位</p>
+            </div>
+            <div class="form-group">
+                <label>确认新密码 <span class="required">*</span></label>
+                <input type="password" name="confirm_password" required>
+            </div>
+            <div class="form-actions">
+                <button type="submit" class="btn btn-primary">修改密码</button>
+                <a href="{{ url_for('dashboard') }}" class="btn btn-secondary">取消</a>
+            </div>
+        </form>
+    </div>
+</div>
+{% endblock %}