feat: 内容源管理优化与条目编辑功能

- 内容源管理：去掉人工录入卡片，AI 密钥保存后可返显并支持小眼睛切换，布局优化
- 内容管理：新增编辑按钮与编辑页，可调整条目全部字段与标签

public/css/main.css

@@ -1594,6 +1594,32 @@ button.chip:hover {
 .field .input {
   width: 100%;
 }
+.ai-key-field {
+  position: relative;
+  flex: 1;
+  min-width: 0;
+}
+.ai-key-field .input {
+  width: 100%;
+  padding-right: 42px;
+}
+.eye-toggle {
+  position: absolute;
+  right: 8px;
+  top: 50%;
+  transform: translateY(-50%);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 4px;
+  border: 0;
+  background: none;
+  cursor: pointer;
+  color: var(--ink-dim);
+}
+.eye-toggle:hover {
+  color: var(--ink);
+}
 .auth-row {
   margin-top: 14px;
   display: flex;

public/js/admin.js

@@ -139,6 +139,19 @@
     });
   }
 
+  document.querySelectorAll("[data-eye-toggle]").forEach(function (btn) {
+    btn.addEventListener("click", function () {
+      var input = btn.closest("form").querySelector("input[name=key]");
+      var show = input.type === "password";
+      input.type = show ? "text" : "password";
+      btn.setAttribute("aria-label", show ? "隐藏密钥" : "显示密钥");
+      var open = btn.querySelector(".eye-open");
+      var closed = btn.querySelector(".eye-closed");
+      if (open) open.hidden = show;
+      if (closed) closed.hidden = !show;
+    });
+  });
+
   document.querySelectorAll("form.source-config").forEach(function (form) {
     form.addEventListener("submit", function (e) {
       e.preventDefault();