fix: repair invite links, social features, messaging + Discord UI overhaul

Phase 1 - Feature Repair:
- Fix member kick/leave: add missing db.delete() call in servers.ts
- Stabilize invite codes: return existing code instead of regenerating
- Fix user search: use LIKE instead of exact match in social.ts
- Wire DM button on FriendsPage to create/navigate to DM channels
- Add cancel outgoing friend request (DELETE endpoint + frontend)
- Add accept/decline friend request actions with WS real-time events
- Fix replyToId persistence in message creation
- Hydrate reactions and replyTo in message queries
- Add joinByCode to API client and serverStore
- Add friend_request_received/accepted WebSocket events

Phase 2 - Discord UI Overhaul:
- Remove stray borders between layout columns
- Replace shadow-sm with shadow-header on content headers
- Replace all bg-gray-*/text-gray-* with Discord color tokens
- Ensure flat color contrast (#1E1F22, #2B2D31, #313338)

Testing:
- Set up vitest + @testing-library/react + jsdom
- Add 17 tests across InviteModal, JoinServer, FriendsPage (all passing)
- Fix vite resolve.extensions to prefer .tsx over stale .js files

packages/web/src/components/chat/Embed.js

@@ -0,0 +1,30 @@
+import { jsx as _jsx, jsxs as _jsxs } from "react/jsx-runtime";
+import { useState, useEffect } from 'react';
+export function Embed({ url }) {
+    const [metadata, setMetadata] = useState(null);
+    const [isLoading, setIsLoading] = useState(true);
+    useEffect(() => {
+        let isMounted = true;
+        // Simple fetch from our new API
+        fetch(`/api/utils/metadata?url=${encodeURIComponent(url)}`, {
+            headers: {
+                'Authorization': `Bearer ${localStorage.getItem('opencord_token')}`
+            }
+        })
+            .then(res => res.json())
+            .then(data => {
+            if (isMounted && data.title) {
+                setMetadata(data);
+            }
+            setIsLoading(false);
+        })
+            .catch(() => {
+            if (isMounted)
+                setIsLoading(false);
+        });
+        return () => { isMounted = false; };
+    }, [url]);
+    if (isLoading || !metadata)
+        return null;
+    return (_jsxs("div", { className: "mt-2 max-w-[520px] bg-discord-bg-secondary rounded-[4px] border-l-4 border-discord-bg-tertiary flex overflow-hidden", children: [_jsxs("div", { className: "flex-1 p-3 min-w-0", children: [metadata.siteName && (_jsx("div", { className: "text-[12px] text-discord-text-normal font-medium mb-1 truncate", children: metadata.siteName })), metadata.title && (_jsx("a", { href: url, target: "_blank", rel: "noopener noreferrer", className: "text-[16px] text-discord-text-link font-semibold hover:underline block mb-2", children: metadata.title })), metadata.description && (_jsx("div", { className: "text-[14px] text-discord-text-normal leading-[1.125rem]", children: metadata.description }))] }), metadata.image && (_jsx("div", { className: "w-[80px] h-[80px] m-3 flex-shrink-0", children: _jsx("img", { src: metadata.image, alt: "", className: "w-full h-full object-cover rounded-[4px]" }) }))] }));
+}