fix(terminal): create PTYs at the client viewport size, not 80x24 (#2023)

New terminals were always spawned by the daemon at the hardcoded 80x24
default and only resized once the client's first resize arrived. On a
slow first mount that leaves a window -- or a stuck state -- where a new
terminal renders far smaller than its pane (e.g. vim in a corner).

Seed the PTY with the client's measured viewport size at creation time
so it is born at the right size and the race window is gone.

- protocol: optional `size` on create_terminal_request. Old daemons
  ignore it and keep 80x24; old clients send nothing. Fully backward
  compatible, no capability gate.
- client: a small last-measured-size cache keyed by serverId+cwd (every
  terminal in a workspace shares the pane) with a most-recent fallback;
  written on fit, read at create.
- server: thread rows/cols through the controller, terminal manager, and
  the worker-thread boundary into the existing size-aware createTerminal.

Tests: cache logic, protocol back-compat parse, controller forwarding.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

packages/app/src/components/terminal-pane.tsx

@@ -21,6 +21,7 @@ import {
   resolvePendingModifierDataInput,
 } from "@/utils/terminal-keys";
 import { getWorkspaceTerminalSession } from "@/terminal/runtime/workspace-terminal-session";
+import { rememberTerminalViewportSize } from "@/terminal/runtime/terminal-size-cache";
 import {
   TerminalStreamController,
   type TerminalStreamControllerStatus,
@@ -635,6 +636,9 @@ export function TerminalPane({
       const normalizedCols = Math.floor(cols);
       const nextSize = { rows: normalizedRows, cols: normalizedCols };
       measuredTerminalSizeRef.current = nextSize;
+      // Seed future terminals in this workspace with the current pane size so they are born at
+      // the right size instead of the daemon's 80x24 default (see terminal-size-cache).
+      rememberTerminalViewportSize({ serverId, cwd, size: nextSize });
       if (!input.shouldClaim || !client || !terminalId || !isWorkspaceFocused || !isAppVisible) {
         return;
       }