feat: discover people tab, privacy settings, and friend request button fix

- Add "Discover People" section to Add Friend tab with user cards, mutual counts, and inline actions
- Add discoverStore for fetching/searching discoverable users across local and federated instances
- Add PrivacyPanel to user settings with discoverability toggle
- Add is_discoverable column to users table with migration
- Fix "Send Friend Request" button vertical alignment using transform centering

packages/web/src/components/modals/UserSettings.tsx

@@ -4,10 +4,11 @@ import { useUIStore } from '../../stores/uiStore';
 import { useAuthStore } from '../../stores/authStore';
 import { AccountPanel } from './settingsPanels/AccountPanel';
 import { VoicePanel } from './settingsPanels/VoicePanel';
+import { PrivacyPanel } from './settingsPanels/PrivacyPanel';
 import { ConnectionsPanel } from './settingsPanels/ConnectionsPanel';
 import { InstancePanel } from './settingsPanels/InstancePanel';
 
-type SettingsTab = 'account' | 'voice' | 'connections' | 'instance';
+type SettingsTab = 'account' | 'voice' | 'privacy' | 'connections' | 'instance';
 
 export function UserSettingsModal() {
   const activeModal = useUIStore((s) => s.activeModal);
@@ -24,7 +25,7 @@ export function UserSettingsModal() {
   useEffect(() => {
     if (isOpen) {
       const requested = modalData.tab as SettingsTab | undefined;
-      if (requested && ['account', 'voice', 'connections', 'instance'].includes(requested)) {
+      if (requested && ['account', 'voice', 'privacy', 'connections', 'instance'].includes(requested)) {
         // Only allow instance tab for admins
         if (requested === 'instance' && !isAdmin) {
           setTab('account');
@@ -59,6 +60,9 @@ export function UserSettingsModal() {
             <button onClick={() => setTab('voice')} className={tabClass('voice')}>
               Voice
             </button>
+            <button onClick={() => setTab('privacy')} className={tabClass('privacy')}>
+              Privacy
+            </button>
             <button onClick={() => setTab('connections')} className={tabClass('connections')}>
               Connections
             </button>
@@ -82,6 +86,7 @@ export function UserSettingsModal() {
         <div className="flex-1 min-w-0 overflow-y-auto scrollbar-thin">
           {tab === 'account' && <AccountPanel />}
           {tab === 'voice' && <VoicePanel />}
+          {tab === 'privacy' && <PrivacyPanel />}
           {tab === 'connections' && <ConnectionsPanel />}
           {tab === 'instance' && isAdmin && <InstancePanel />}
         </div>

packages/web/src/components/modals/settingsPanels/PrivacyPanel.tsx

@@ -0,0 +1,53 @@
+import { useState, useEffect } from 'react';
+import { useAuthStore } from '../../../stores/authStore';
+import { api } from '../../../api/client';
+import { Toggle } from '../../ui/Toggle';
+
+export function PrivacyPanel() {
+  const user = useAuthStore((s) => s.user);
+  const setUser = useAuthStore((s) => s.setUser);
+  const [discoverable, setDiscoverable] = useState(user?.discoverable !== false);
+  const [saving, setSaving] = useState(false);
+
+  useEffect(() => {
+    setDiscoverable(user?.discoverable !== false);
+  }, [user?.discoverable]);
+
+  const handleToggle = async (enabled: boolean) => {
+    setDiscoverable(enabled);
+    setSaving(true);
+    try {
+      const updated = await api.users.update({ discoverable: enabled });
+      setUser(updated);
+    } catch {
+      // Revert on failure
+      setDiscoverable(!enabled);
+    } finally {
+      setSaving(false);
+    }
+  };
+
+  return (
+    <div className="space-y-5">
+      <div>
+        <div className="text-[11px] font-semibold text-txt-tertiary uppercase tracking-wider mb-1.5">
+          Discovery
+        </div>
+        <div className="rounded-lg bg-white/[0.03] border border-white/[0.04] p-3.5">
+          <div className="flex items-center justify-between py-1">
+            <div className="flex-1 mr-4">
+              <div className="text-sm text-txt-primary">Allow others to find my profile</div>
+              <div className="text-xs text-txt-tertiary mt-0.5">
+                When enabled, your profile appears in Discover People. Others can always add you by exact username.
+              </div>
+            </div>
+            <Toggle enabled={discoverable} onChange={handleToggle} />
+          </div>
+          {saving && (
+            <div className="text-xs text-txt-tertiary mt-2">Saving...</div>
+          )}
+        </div>
+      </div>
+    </div>
+  );
+}