Agents app should persist layout

[mjbvz]

Type: Bug

1. Open agents app
2. Make sessions list wider
3. Reload

Bug
Sessions list is small again

VS Code version: Agents - Insiders 1.118.0-insider (Universal) (1b91e5e, 2026-04-27T13:56:59+02:00)
OS version: Darwin arm64 25.4.0
Modes:

System Info

Item	Value
CPUs	Apple M2 Max (12 x 2400)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x106b [Google Inc. (Apple)], DEVICE=0x0000 [ANGLE (Apple, ANGLE Metal Renderer: Apple M2 Max, Version 26.4.1 (Build 25E253))], DRIVER_VENDOR=Apple, DRIVER_VERSION=26.4.1 ACTIVE Machine model name: Mac Machine model version: 14.6 direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: enabled_on trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	3, 4, 5
Memory (System)	64.00GB (0.10GB free)
Process Argv	--new-window --folder-uri file:///Users/matb/projects/vscode-markdown-languageservice --crash-reporter-id dbfb96d5-6070-4b22-9920-d3fbdda08403
Screen Reader	no
VM	0%

[vs-code-engineering]

Hi @mjbvz. As a member of the team, you can help us triage this issue by referring to https://github.com/microsoft/vscode-copilot/wiki/Copilot-Inbox-Tracker and assigning an owner directly.