feat(chat): rich shared-media view, status selector, drag-drop upload + fixes

Chat / shared media:
- Media/Docs/Links: clean underline tabs (green active), audio & video now
  classified as Media and rendered as tiles (download + headphone/play +
  duration) instead of broken-image glyphs; image thumbnails -> lightbox
- Drag-and-drop a file/video/image onto a conversation to send it
- Fix: removed #chatPanel{position:relative} override that collapsed the
  conversation pane (messages spilled into a clipped right-edge strip)
- "Media, links & docs" row cleaned up (no folder/placeholder icon); media
  popup keeps the back arrow, drops the redundant close button

Presence / status:
- Single current-status row with an arrow that expands Available/Away/On leave
- On leave = circle with minus, In a call = solid red indicators
- Fix: selected-status tick now follows the chosen option

Icons: added headphones + play; bumped icons.js cache-bust to v4

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/db.js

@@ -213,6 +213,11 @@ try { db.exec('ALTER TABLE conversations ADD COLUMN admin_only INTEGER NOT NULL
 try { db.exec('ALTER TABLE messages ADD COLUMN poll_id TEXT'); } catch (e) { /* exists */ }
 // Activity/event lines (e.g. 'call-start','call-end') render as centered system messages.
 try { db.exec('ALTER TABLE messages ADD COLUMN msg_type TEXT'); } catch (e) { /* exists */ }
+// Deleted ("delete for everyone"): the row stays so threads/ordering hold, but body+attachment
+// are cleared and clients render a "This message was deleted" placeholder.
+try { db.exec('ALTER TABLE messages ADD COLUMN deleted INTEGER NOT NULL DEFAULT 0'); } catch (e) { /* exists */ }
+// User-set presence status: 'active' | 'away' | 'onleave'. ('incall' is derived live, not stored.)
+try { db.exec("ALTER TABLE users ADD COLUMN status TEXT NOT NULL DEFAULT 'active'"); } catch (e) { /* exists */ }
 db.exec(`
 CREATE TABLE IF NOT EXISTS polls (
   id TEXT PRIMARY KEY,
@@ -301,4 +306,14 @@ CREATE TABLE IF NOT EXISTS push_subscriptions (
 CREATE INDEX IF NOT EXISTS idx_push_user ON push_subscriptions(user_id);
 `);
 
+// Favourite conversations (per user). target = 'dm:<userId>' or 'group:<groupId>'.
+db.exec(`
+CREATE TABLE IF NOT EXISTS favorites (
+  user_id TEXT NOT NULL,
+  target TEXT NOT NULL,
+  created_at INTEGER NOT NULL,
+  PRIMARY KEY (user_id, target)
+);
+`);
+
 module.exports = db;