Add version display to web UI sidebar (v0.36.18)

- Add version footer to sidebar bottom-left with Gitea icon link
- Fetch relay version from NIP-11 relay info document
- Link opens https://next.orly.dev in new tab
- Responsive design hides version text on medium screens

Files modified:
- app/web/src/api.js: Add fetchRelayInfo() function
- app/web/src/Sidebar.svelte: Add version display with Gitea SVG icon
- app/web/src/App.svelte: Add relayVersion state and fetch on init
- pkg/version/version: Bump to v0.36.18

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/web/src/Sidebar.svelte

@@ -2,6 +2,7 @@
     export let isDarkTheme = false;
     export let tabs = [];
     export let selectedTab = "";
+    export let version = "";
 
     import { createEventDispatcher } from "svelte";
     const dispatch = createEventDispatcher();
@@ -41,6 +42,15 @@
             {/each}
         </div>
     </div>
+    {#if version}
+        <a href="https://next.orly.dev" target="_blank" rel="noopener noreferrer" class="version-link">
+            <svg class="gitea-icon" viewBox="0 0 640 640" fill="currentColor" xmlns="http://www.w3.org/2000/svg">
+                <path d="M395.9 484.2l-126.9-61c-12.5-6-17.9-21.2-11.8-33.8l61-126.9c6-12.5 21.2-17.9 33.8-11.8 17.2 8.3 27.1 13 27.1 13l-.1-51.6s-.1-30.3 21.7-32.1c-.1 0 74-3 74-3s30.1-1.5 32.1 22.4c0 0 3.9 74.6 3.9 74.6s1.2 22.8-23.2 30c0 0-13.6 3.9-20.6 6-13.6 4.1-26.1-9-24.6-24.6l3.5-42.9-31.3 66.5-31.4 65.2c-4.2 8.7-1.1 18.8 7 24.2l32.9 21.1c11 7 .2 18.2-7.7 37.1l-19.4 48.6z"/>
+                <path d="M286.1 499.2l127-60.9c12.5-6 17.9-21.3 11.9-33.8l-61-126.9c-6-12.5-21.2-17.9-33.8-11.9-17.2 8.3-27.1 13-27.1 13l.1-51.6s.1-30.3-21.7-32.1c.1 0-74-3-74-3s-30.1-1.5-32.1 22.4c0 0-3.9 74.6-3.9 74.6s-1.2 22.8 23.2 30.1c0 0 13.6 3.9 20.6 5.9 13.6 4.1 26.1-9 24.6-24.6l-3.5-42.9 31.3 66.5 31.4 65.2c4.2 8.8 1 18.8-7 24.2l-32.9 21.1c-11 7.1-.2 18.3 7.7 37.1l19.2 48.6z"/>
+            </svg>
+            <span class="version-text">v{version}</span>
+        </a>
+    {/if}
 </aside>
 
 <style>
@@ -152,4 +162,50 @@
             justify-content: flex-start;
         }
     }
+
+    .version-link {
+        position: absolute;
+        bottom: 0;
+        left: 0;
+        right: 0;
+        display: flex;
+        align-items: center;
+        gap: 0.5rem;
+        padding: 0.75em 1em;
+        color: var(--muted-foreground);
+        text-decoration: none;
+        font-size: 0.8em;
+        transition: color 0.2s;
+    }
+
+    .version-link:hover {
+        color: var(--text-color);
+    }
+
+    .gitea-icon {
+        width: 1.2em;
+        height: 1.2em;
+        flex-shrink: 0;
+    }
+
+    .version-text {
+        white-space: nowrap;
+    }
+
+    @media (max-width: 1280px) {
+        .version-text {
+            display: none;
+        }
+
+        .version-link {
+            justify-content: flex-start;
+            padding-left: 1.25em;
+        }
+    }
+
+    @media (max-width: 640px) {
+        .version-text {
+            display: inline;
+        }
+    }
 </style>