feat(profile): 'Active now' / 'Last active …' line from presence (#150)

One line under the handle in the user profile popover, from the presence the
SDK already receives (currently_active + last_active_ago): 'Active now',
'Active just now', 'Last active 12 min ago / 3 hours ago / yesterday / 5 days
ago / over a month ago'. Nothing is shown without presence data or for an
offline user with no timestamp (Hide Online Status users), so nothing new is
exposed; re-renders on the existing presence events, no polling. Wording
unit-tested; verified headless ('Active now' for an online member).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

src/app/utils/lastActive.test.ts

@@ -0,0 +1,53 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { describeLastActive } from './lastActive';
+
+const now = 1_800_000_000_000;
+test('wording buckets', () => {
+  assert.equal(describeLastActive(undefined), null);
+  assert.equal(describeLastActive({ presence: 'offline', active: false }), null);
+  assert.equal(describeLastActive({ presence: 'offline', active: false, lastActiveTs: 0 }), null);
+  assert.equal(
+    describeLastActive({ presence: 'online', active: true, lastActiveTs: now }, now),
+    'Active now',
+  );
+  assert.equal(
+    describeLastActive({ presence: 'online', active: false, lastActiveTs: now - 20_000 }, now),
+    'Active just now',
+  );
+  assert.equal(
+    describeLastActive(
+      { presence: 'unavailable', active: false, lastActiveTs: now - 12 * 60_000 },
+      now,
+    ),
+    'Last active 12 min ago',
+  );
+  assert.equal(
+    describeLastActive(
+      { presence: 'offline', active: false, lastActiveTs: now - 3 * 3_600_000 },
+      now,
+    ),
+    'Last active 3 hours ago',
+  );
+  assert.equal(
+    describeLastActive(
+      { presence: 'offline', active: false, lastActiveTs: now - 26 * 3_600_000 },
+      now,
+    ),
+    'Last active yesterday',
+  );
+  assert.equal(
+    describeLastActive(
+      { presence: 'offline', active: false, lastActiveTs: now - 5 * 86_400_000 },
+      now,
+    ),
+    'Last active 5 days ago',
+  );
+  assert.equal(
+    describeLastActive(
+      { presence: 'offline', active: false, lastActiveTs: now - 40 * 86_400_000 },
+      now,
+    ),
+    'Last active over a month ago',
+  );
+});

src/app/utils/lastActive.ts

@@ -0,0 +1,24 @@
+/**
+ * [Gitea #150] "Active now" / "Last active 12 min ago" from presence.
+ * Returns null when there is nothing honest to say: no presence data, an
+ * offline user with no timestamp (e.g. someone hiding their online status).
+ */
+export const describeLastActive = (
+  presence: { presence: string; active: boolean; lastActiveTs?: number } | undefined,
+  now = Date.now(),
+): string | null => {
+  if (!presence) return null;
+  if (presence.presence === 'online' && presence.active) return 'Active now';
+  const ts = presence.lastActiveTs;
+  if (!ts || ts <= 0) return null;
+  const ago = Math.max(0, now - ts);
+  const min = Math.round(ago / 60_000);
+  if (min < 1) return 'Active just now';
+  if (min < 60) return `Last active ${min} min ago`;
+  const hours = Math.round(min / 60);
+  if (hours < 24) return `Last active ${hours} ${hours === 1 ? 'hour' : 'hours'} ago`;
+  const days = Math.round(hours / 24);
+  if (days === 1) return 'Last active yesterday';
+  if (days < 30) return `Last active ${days} days ago`;
+  return 'Last active over a month ago';
+};