Workspaces not restored from previous session on macOS

[cdamus]

Bug Description:

On macOS it is expected that, unless configured otherwise in the application's preferences or the system preferences, when opening an application it will open again the same windows as were open when the application was last quit.

TheiaIDE does not provide any preference to control this behaviour and it does not seem to follow my system preference for restoring application windows. When I have multiple workspaces open in TheiaIDE and quit it, upon reopening TheiaIDE I get only the last-opened workspace. And that is in a new stage of its own (but that is a separate matter, #458).

Steps to Reproduce:

1. Launch TheiaIDE.
2. Open a workspace (say, A).
3. Open another workspace (say, B).
4. Quit TheiaIDE.
5. Open TheiaIDE again.
6. See only workspace B open.

Additional Information

• Operating System: macOS Sequoia 15.3 on M4 Max
• Theia Version: 1.58.100.202