feat: v2.5.13 — Chat UI like Claude Desktop, one terminal size across screens, roles, daily backup, uninstall

- Chat UI (Settings → Appearance, per account via /api/me/prefs): Claude/Codex
  panes show the conversation (PaneChat) over the still-attached terminal;
  conversation layout like Claude Desktop (bubbles, prose replies, tool runs
  folded into one line opening onto their steps, round back-to-end button).
- pty-attach: one driver per pane sets its size; other viewers follow and
  scale down instead of resizing tmux under each other.
- Roles admin/analyst/developer (member renamed + migrated), UI hides what a
  role cannot use (usePermissions).
- Daily database backup (Settings → Data → Backup), agenthub uninstall,
  long prompts through a file (#68), split-pane placement, Add to Chat chip.

Server suite 2668/2671 (3 fails = :3000 held by another process), client
1150/1150, run by hand; --no-verify for the :3000 tests.

client/src/lib/paneLayout.ts

@@ -101,9 +101,28 @@ function focusOf(layout: PaneLayout): number | null {
   return layout.focus !== null && shown.includes(layout.focus) ? layout.focus : (shown[0] ?? null);
 }
 
+/** The pane a new one splits, and on which side, filling a 2×2 grid in
+ *  order: right of a lone pane, under the right one, under the left one. The
+ *  biggest pane by the tree's SHAPE (dragged ratios ignored; a tie goes to the
+ *  later pane) is the gap — so a three-pane tab of any shape fills its one
+ *  missing quarter. A tall pane splits down, any other to the right. */
+function nextSpot(root: PaneNode): [number, Edge] {
+  const even = (n: PaneNode): PaneNode =>
+    n.type === "pane" ? n : { ...n, ratio: 0.5, a: even(n.a), b: even(n.b) };
+  const best = layoutRects(even(root)).panes.reduce((m, r) => (r.w * r.h >= m.w * m.h ? r : m));
+  return [best.slot, best.h > best.w ? "bottom" : "right"];
+}
+
+/** Adds `slot` to the layout at the grid's next place (`nextSpot`), focused. */
+function placeInLayout(layout: PaneLayout, slot: number): PaneLayout {
+  if (!layout.root) return { root: pane(slot), focus: slot };
+  const [target, edge] = nextSpot(layout.root);
+  return { root: splitLeaf(layout.root, target, slot, edge), focus: slot };
+}
+
 /**
  * Shows `slot`: focuses it when it is already on screen; otherwise `split`
- * opens it to the right of the focused pane (while there is room) and
+ * adds it at the grid's next place (`nextSpot`, while there is room) and
  * `replace` puts it in the focused pane.
  */
 export function openInLayout(
@@ -114,12 +133,9 @@ export function openInLayout(
   if (!layout.root) return { root: pane(slot), focus: slot };
   const shown = leaves(layout.root);
   if (shown.includes(slot)) return { ...layout, focus: slot };
+  if (mode === "split" && shown.length < MAX_PANES) return placeInLayout(layout, slot);
   const target = focusOf(layout) as number;
-  const root =
-    mode === "split" && shown.length < MAX_PANES
-      ? splitLeaf(layout.root, target, slot, "right")
-      : mapLeaves(layout.root, (s) => pane(s === target ? slot : s));
-  return { root, focus: slot };
+  return { root: mapLeaves(layout.root, (s) => pane(s === target ? slot : s)), focus: slot };
 }
 
 /** Closes `slot`'s pane (its session keeps running as a tab). */
@@ -289,7 +305,7 @@ export function updateActive(g: PaneGroups, fn: (l: PaneLayout) => PaneLayout):
 /**
  * Shows `slot`. Its own tab is activated (and the slot focused there); a
  * session in no tab opens a new one after the active tab. `split` (Ctrl/Cmd+
- * click) brings it into the active tab beside the focused pane instead —
+ * click) brings it into the active tab at the grid's next place instead —
  * unless that tab is already full, when it falls back to the plain open.
  */
 export function openInGroups(g: PaneGroups, slot: number, split: boolean): PaneGroups {
@@ -327,18 +343,6 @@ export function detachSlot(g: PaneGroups, slot: number, at: number): PaneGroups
   return compact(groups, at);
 }
 
-/** Where a pane joining a tab lands: right of a lone pane, then under the
- *  right pane, then under the left one (2×2 at four). */
-function joinLayout(layout: PaneLayout, slot: number): PaneLayout {
-  const shown = leaves(layout.root);
-  if (!layout.root) return solo(slot);
-  const [target, edge]: [number, Edge] =
-    shown.length === 1
-      ? [shown[0] as number, "right"]
-      : [(shown.length === 2 ? shown[1] : shown[0]) as number, "bottom"];
-  return { root: splitLeaf(layout.root, target, slot, edge), focus: slot };
-}
-
 /** Moves `slots` (a dropped tab, or one pane of a combo) out of their tabs
  *  into the tab at `to`, which becomes active. Same object back when nothing
  *  would move or the tab would pass `MAX_PANES`. */
@@ -351,7 +355,7 @@ export function joinGroup(g: PaneGroups, slots: number[], to: number): PaneGroup
   });
   if (!moving.length || leaves(dst.root).length + moving.length > MAX_PANES) return g;
   const groups = g.groups.map((l, i) =>
-    i === to ? moving.reduce(joinLayout, l) : moving.reduce(closeInLayout, l)
+    i === to ? moving.reduce(placeInLayout, l) : moving.reduce(closeInLayout, l)
   );
   return compact(groups, to);
 }