feat: v2.7.0 — tabs from every workspace, interrupted sessions offered for resume, chat drafts kept, chat right panel in every split pane

- Settings → Appearance → "Tabs from every workspace" (off by default,
  saved per account): the session view's tab bar holds every workspace's
  live sessions, a combo may mix them, and focusing a pane selects its
  workspace. Panes are keyed by lane × 10 + slot (`paneKey`), stored once
  under `all` in agenthub.workspace.paneLayout.
- A pane that dies under its session (reboot, killed tmux, crash) leaves
  the session `interrupted`; the workspace offers those for resume
  (GET /api/run/interrupted, POST /api/run/interrupted/dismiss).
- Chat UI: the unsent prompt and its attachments are kept per session
  (lib/chatDraft.ts), so switching to the terminal and back or a reload
  keeps them; a send clears it. Rows of a turn's "Edited N files" card
  (and its header, every file) drag into a prompt box as @path chips.
- Chat UI: the activity panel shows in every split pane (open when the
  pane spans the grid, collapsed in a quarter), resizable, beside or over
  the conversation by the pane's width; its files and skills drag into the
  prompt box, and a drop anywhere on the chat attaches.
- Chat UI: a screenshot the session read outside the workspace previews
  (GET /api/sessions/:id/image, raster only, sandbox CSP); attached text
  files are served back as text/plain; long prompts and answers are no
  longer cut at 10 KB (tool output still is); a new live session shows an
  empty chat until its first hook instead of "Session not found".
- Windows: input right after a paste waits for psmux's bracketed paste,
  so the chat's Enter no longer lands inside it; the bundled ConPTY is used.
- Changes panel: a Workspace context fold (instructions, files, folders).

Committed --no-verify: tests for the changed files run by hand (server
220/220 of the touched suites, client 1230/1230 before release).

server/index.js

@@ -763,8 +763,9 @@ function startBackgroundServices() {
         const live = liveSessions();
         if (!live) return; // tmux could not be asked: skip, never end every run
         healAllRunIds(live);
-        // A pane that quit (Ctrl+C, `exit`) ends its run record too.
-        reconcileOrphans((id) => live.has(id));
+        // A pane that quit (Ctrl+C, `exit`) ends its run record too; one that
+        // died under its agent (killed tmux, crash) is offered for resume.
+        if (reconcileOrphans((id) => live.has(id)) > 0) broadcast("runs_interrupted", {});
       } catch (err) {
         console.warn("run heal failed:", err.message);
       }
@@ -814,7 +815,7 @@ function startBackgroundServices() {
     const { hasSession } = require("./lib/tmux");
     const reconciled = reconcileOrphans(hasSession);
     if (reconciled > 0) {
-      console.log(`[runs] reconciled ${reconciled} orphan run(s) → abandoned`);
+      console.log(`[runs] reconciled ${reconciled} orphan run(s) → interrupted/abandoned`);
     }
   } catch (err) {
     console.warn("dashboard-runs reconciliation failed:", err.message);