Groups own pane/grid layout (idea)

[mortenaslo]

Idea

Should session groups also reflect the window/pane setup? In other words, a group would own its visible pane/grid structure, and switching groups would swap the entire terminal layout — effectively hiding shells that aren't in the active group.

Current behavior

• Groups are display-only — they affect sidebar grouping (None / Strip / Inline headers) but all live sessions are visible in the terminal area regardless of group.
• The grid layout (Single / TwoByTwo / etc.) is a single global setting persisted to AppState.LastLayout.

Proposed behavior

• Each group could store its own layout mode + which sessions are visible/arranged in its panes.
• Selecting a group would:
  • Show only that group's sessions in the terminal area.
  • Restore that group's saved pane arrangement.
• Sessions outside the active group remain alive (PTY running, output indexed, alerts firing) — just not rendered until you switch back.

Open questions

• Is this actually useful, or does the current group-as-sidebar-decoration model cover the real workflows? The motivating use case would be juggling many projects where you want to context-switch between, say, a 4-pane "frontend" group and a 2-pane "infra" group without manually rearranging.
• How would this interact with cross-group drag-to-reassign (recently added in inline mode)?
• Per-group layout persistence would need new fields on SessionGroup and a migration of AppState.LastLayout semantics.

Status

Just an idea — not sure it's actually needed. Filing so it's not lost.

[AThraen]

Shipped in v0.5.0.