feat(web): discord-style chat, members pane, invitations and optimistic send [CI]

- chat: left-aligned discord-style messages with grouped senders, hover
  actions, an auto-growing composer and file cards
- send: render messages and files locally first and replace the
  placeholder when the worker publishes the real item; failures keep the
  text with a retry action
- navigation: space rail plus a flatter channel list with the space name
  header and collapsible groups
- members: right pane tabs (files / members) grouped by online, offline
  and pending users, with a prominent invite action and a top bar shortcut
- notifications: toast host for invite results; invitees get a toast with
  an accept action, and the invitation payload now carries the space name
  and inviter inside the encrypted grant
- users over devices: drop device names, the device list and device
  rename/release; senders show the account (guests show as guest) and the
  share panel only keeps links
- follow contract 7.0.0 (max_members, members_used, members_full, /join)
- docs: ui-design and frontend updated for the new layout and concepts

web/src/core-bridge/worker/shareRead.ts

@@ -68,7 +68,7 @@ async function loadSealedManifest(resource: SavedResource, session: ChannelSessi
       const entry = manifest.items[index];
       if (!entry) throw new Error('invalid_manifest_item');
       if (entry.t === 'text' && typeof entry.text === 'string' && Number.isSafeInteger(entry.ts)) {
-        const item: TextItem = { id: `manifest-text-${index}`, kind: 'text', ts: entry.ts, deviceId: '创建者', state: { kind: 'complete' }, text: entry.text };
+        const item: TextItem = { id: `manifest-text-${index}`, kind: 'text', ts: entry.ts, state: { kind: 'complete' }, text: entry.text };
         publishShare(resource.id, { t: 'item', item });
       } else if (entry.t === 'file' && typeof entry.id === 'string' && typeof entry.size === 'number' && Number.isSafeInteger(entry.size)) {
         const detail = byId.get(entry.id);