feat: add a warning banner on the login page for misconfigured cookies

docs/.vitepress/config.ts

@@ -25,7 +25,13 @@ export default defineConfig({
 							{ text: 'Docker', link: '/install/docker' },
 						],
 					},
-					{ text: 'Configuration', link: '/configuration' },
+					{
+						text: 'Configuration',
+						link: '/configuration',
+						items: [
+							{ text: 'Common Issues', link: '/configuration/common-issues' },
+						],
+					},
 					{ text: 'Nix', link: '/Nix' },
 					{ text: 'NixOS', link: '/NixOS-options' },
 					{

docs/configuration/common-issues.md

@@ -0,0 +1,25 @@
+---
+title: Common Issues
+description: Common issues and their solutions
+---
+
+# Common Issues and Their Solutions
+This document outlines some common issues users may encounter while using Headplane, along with their solutions.
+
+## Login does not work
+::: tip
+Headplane tries to detect misconfigurations and will surface a warning banner on
+the login page if it detects any abnormalities. You may see a banner like this:
+<figure>
+    <img class="dark-only" src="../assets/login-banner-dark.png" />
+    <img class="light-only" src="../assets/login-banner-light.png" />
+    <figcaption>Login Warning Banner</figcaption>
+</figure>
+:::
+
+If you attempt to log in to Headplane but nothing happens, it may be due to a
+misconfiguration of the server cookie settings. In your Headplane configuration,
+ensure that `server.cookie_secure` is set appropriately based on how you are
+accessing Headplane:
+- Serving over HTTPS: `cookie_secure` should be enabled (`true`).
+- Serving over HTTP: `cookie_secure` should be disabled (`false`).