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/client/src/daemon-client.ts

@@ -4275,7 +4275,13 @@ export class DaemonClient {
     cwd: string,
     name?: string,
     requestId?: string,
-    options?: { agentId?: string; command?: string; args?: string[]; workspaceId?: string },
+    options?: {
+      agentId?: string;
+      command?: string;
+      args?: string[];
+      workspaceId?: string;
+      size?: { rows: number; cols: number };
+    },
   ): Promise<CreateTerminalPayload> {
     const resolvedRequestId = this.createRequestId(requestId);
     const message = SessionInboundMessageSchema.parse({
@@ -4286,6 +4292,7 @@ export class DaemonClient {
       command: options?.command,
       args: options?.args,
       ...(options?.workspaceId !== undefined ? { workspaceId: options.workspaceId } : {}),
+      ...(options?.size !== undefined ? { size: options.size } : {}),
       requestId: resolvedRequestId,
     });
     return this.sendCorrelatedRequest({