feat(menu): #79 slice 3 — Look & Feel › Auto theme (completes #79)

Adds an "Auto theme (on/off)" row to Look & Feel and an `autotheme`
submenu: toggle the feature, pick the day/night themes (from
`nomarchy-theme-sync list`), and set the sunrise/sunset times (HH:MM,
validated). This is the menu surface over settings.autoTheme, completing
the auto time-of-day theme feature (slices: CLI / timer / menu).

Enabling writes the flag and defaults the summer-day/summer-night pair
--no-switch, then runs `auto --force`, so a single rebuild both installs
the timer and applies the correct theme for now. Disabling is instant
(--no-switch): the flag flips and `auto` self-gates, so the lingering
timer no-ops until the next rebuild. Day/night/time writes are live
--no-switch (read by `auto` at tick time).

Verification: V1 — HM generation builds (bash -n on nomarchy-menu at
build) + bash -n on the built menu. Logic test with stubbed
rofi/theme-sync/notify: selecting the toggle from off runs exactly `set
day/night/enable ... --no-switch` then `auto --force` — the intended
one-rebuild path. V0 flake check green. All three #79 slices shipped;
the live timer switch across sunset is a real-session (V3) check on a
Nomarchy machine.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

agent/JOURNAL.md

@@ -17,6 +17,27 @@ Template:
 
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+## 2026-07-10 — #79 slice 3: Look & Feel › Auto theme menu (#79 complete)
+- **Task:** BACKLOG #79 slice 3 — the menu; completes the feature.
+- **Did:** `rofi.nix` — "Auto theme (on/off)" row in Look & Feel + an
+  `autotheme)` submenu: toggle, pick day/night (from
+  `nomarchy-theme-sync list`), set sunrise/sunset (HH:MM input, validated).
+  Enable writes the flag + defaults the summer pair `--no-switch`, then
+  `exec auto --force` — one rebuild installs the timer AND applies the right
+  theme. Disable is instant `--no-switch` (`auto` self-gates; the lingering
+  timer no-ops). Day/night/times are live `--no-switch`.
+- **Verified:** **V1** — HM generation builds (`writeShellScriptBin` bash -n
+  on nomarchy-menu passes) + bash -n on the built menu. **Logic test**
+  (stubbed rofi/theme-sync/notify): selecting "Auto theme (off)" runs exactly
+  `set day summer-day`, `set night summer-night`, `set enable true`
+  (all `--no-switch`), then `auto --force` — the intended one-rebuild path.
+  Disable path is static-clear (set false `--no-switch`, no `auto`); a
+  stateful-stub dynamic test would loop (stub doesn't reflect the flip). V0
+  flake check green. **#79 collapsed to `[blocked:hw]`** (all 3 slices done;
+  only live-session switch remains, needs a Nomarchy machine).
+- **Pending:** V3 real-session (timer switches day↔night across sunset).
+- **Next suggestion:** NEXT head #76/#79 both `[blocked:hw]`; QA/PROPOSED.
+
 ## 2026-07-10 — #79 slice 2: auto-theme systemd timer
 - **Task:** BACKLOG #79 slice 2 — the timer/hook.
 - **Did:** `modules/home/autotheme.nix` (imported in home default.nix):