feat(rituals): Phase 5 — morning triage, evening wind-down, autostart

Three opt-in rituals, all default OFF. Research-anchored (Barkley's
point-of-performance, Sweller cognitive-load theory, Newport shutdown
ritual, Gollwitzer implementation intentions, Thaler/Sunstein nudge
with informed consent for the ADHD audience).

Morning triage: modal gated on ritualsMorning toggle, configurable
trigger time (default 08:00 to respect ADHD sleep inertia rather than
the spec's 06:00), "pick up to three for today" with a gentle swap
message on the fourth attempt. Skip sets last-shown-today so it never
re-prompts the same calendar day. last-shown persists via kon_storage.

Evening wind-down: dedicated page, user-triggered only (tray menu +
Settings button). Mechanical closure + physical reset + intentional
cue — the whole Newport template. Open loops are read-only reflection;
Tasks page owns transactions. Copy is additive throughout: "you
finished X today", never "you didn't finish Y".

Autostart: tauri-plugin-autostart registered (LaunchAgent on macOS,
.desktop on Linux, registry Run on Windows). No bespoke Rust commands
— frontend calls the plugin's invoke-handlers directly. Toggle in
Settings is one-way (click → OS call → state update) to avoid the UI
lying during the round-trip. First-run presents a forced-choice prompt
for all three options, with "skip all" escape hatches per step.

Copy audit against RSD literature: no "overdue", "failed", or
day-to-day comparison framing anywhere in ritual surfaces.

Post-v0.1 ideas captured in the roadmap: calendar integration
(read-only ICS as interim, cloud sync parked) and right-click-to-task
(in-app simple, system-wide a separate phase).

src-tauri/src/commands/rituals.rs

@@ -0,0 +1,43 @@
+//! Phase 5 of the feature-complete roadmap: start- and shutdown-rituals.
+//!
+//! Layer-1 scope is narrow. The frontend owns rendering and logic; this
+//! module only persists the "last date the morning triage modal was
+//! shown" sentinel so the modal can refuse to re-prompt on the same
+//! calendar day. Task queries re-use `list_tasks_cmd` with client-side
+//! filtering rather than adding a second query path.
+//!
+//! Stored under the existing SQLite settings table via
+//! `kon_storage::{get_setting, set_setting}` — same bag as
+//! `kon_preferences`.
+
+use kon_storage::{get_setting, set_setting};
+
+use crate::AppState;
+
+const LAST_TRIAGE_KEY: &str = "kon_morning_triage_last_shown";
+
+/// Returns the YYYY-MM-DD date string stored on the last successful
+/// morning triage dismissal, or `None` if the user has never been
+/// shown the modal.
+#[tauri::command]
+pub async fn get_last_morning_triage(
+    state: tauri::State<'_, AppState>,
+) -> Result<Option<String>, String> {
+    get_setting(&state.db, LAST_TRIAGE_KEY)
+        .await
+        .map_err(|e| e.to_string())
+}
+
+/// Records that the morning triage modal was shown (and either skipped
+/// or completed) on `date`. Caller is responsible for passing a valid
+/// YYYY-MM-DD string in the user's local timezone — Rust deliberately
+/// stays timezone-agnostic here so the frontend retains control.
+#[tauri::command]
+pub async fn mark_morning_triage_shown(
+    state: tauri::State<'_, AppState>,
+    date: String,
+) -> Result<(), String> {
+    set_setting(&state.db, LAST_TRIAGE_KEY, &date)
+        .await
+        .map_err(|e| e.to_string())
+}