feature_name: tauri-pi-desktop-client
problem_statement: >
  The current Noctalia panel is not reliably interactive or testable, while
  users need a feature-equivalent Pi desktop client that works independently
  of any status bar.
constraints:
  - The bridge remains the only Pi process/session/recovery owner.
  - The Tauri host uses only the local Unix bridge client and never opens TCP.
  - Noctalia is an optional compact launcher/status compatibility layer.
  - Folder selection is explicit and canonicalized by the bridge.
  - Pi owns model, thinking, queue behavior, approvals, and extension policy.
  - TUI-only custom extension UI must show unsupported and never auto-approve.
out_of_scope:
  - Pixel-identical terminal TUI rendering.
  - Arbitrary custom TUI extension component rendering.
  - Auto-starting every remembered non-Home folder at login.
key_decisions:
  - decision: One default composer
    rationale: Mirror the confirmed TUI workflow without bridge-owned prompt/steer decisions.
  - decision: Tauri owns the primary UI
    rationale: Native host IPC plus frontend/unit/E2E testing is more reliable than a declarative status-bar panel.
  - decision: Noctalia is a compatibility shim
    rationale: It displays compact status and opens/focuses the standalone client without owning UI behavior.
  - decision: Persist remembered folders and last selection
    rationale: Remove manual ID/folder setup while preserving explicit selection.
  - decision: Home agent is always running
    rationale: Provide an immediately available default Pi instance.