chore: v1-prep hygiene sweep — LICENSE (MIT), fixtures under tools/, doc staleness

Three-way audit ahead of v1 (structure/necessity, docs-vs-code drift,
mechanical checkers) came back clean: zero dead files, zero doc hard
errors, all 92 options documented, all consistency checkers green, no
untracked files. What it did surface, fixed here:

- LICENSE was missing entirely — the one hard launch blocker. MIT
  (Bernardo's call), pointer at the README foot.
- checks/ was the only top-level dir outside the documented layout rule;
  its two state-legacy-name fixtures moved to tools/fixtures/ (Bernardo
  chose move over documenting an exception), flake.nix refs + drift
  messages updated.
- Doc staleness: two leftover "theme-state" leads (HARDWARE.md,
  REQUIREMENTS.md) now say state.json; VISION Theme C charge-limit row
  gets its ✓; VISION agent-slices datestamp bumped.
- The idle.nix miniTransition duplication (same binary name, lossy
  subset of the real display-transition tool) is deliberately NOT
  refactored here — filed as PROPOSED #150 with the audit evidence.

Wallpapers-in-repo (97 MB) is the known LATER artifact-split item, not
re-filed.

Verification: V0 — nix flake check --no-build green after the fixture
move (state-legacy-name's eval asserts exercise the new paths); doc
edits prose-reviewed. Audits by three Sonnet passes; triage on Fable.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

agent/BACKLOG.md

@@ -185,6 +185,25 @@ If that count is zero over a few weeks post-linger, **close this unbuilt**. If i
 is not, the upstream issue has sat ten months on vaxerski's "that will cause a
 segfault no?" and a reproducer would be worth more than a local guard.
 
+### 150. Extract the display-transition tool — idle.nix carries a lossy copy under the same name
+
+Found by the 2026-07-17 structural audit. `modules/home/idle.nix:23-53` defines
+`miniTransition`, a ~22-line `writeShellScriptBin` named
+**`nomarchy-display-transition`** — the same binary name as the real ~175-line
+tool in `modules/home/hyprland.nix:136-310` — implementing only
+`undock|enable`, with none of the full tool's safety: no logging, no
+lid-inhibitor gate, no `restore_keyboards`, no workspace moves, no
+failure dump. The comment says why: "a mini transition avoids a circular
+import on hyprland.nix". No PATH collision today (the mini is never installed;
+it is baked by store path into hypridle's wake tool via `display-tools.nix`),
+but nothing asserts the two stay behaviourally consistent, and this is the
+subsystem where #100/#142/#148 all lived. Pitch: extract the full tool into
+its own module file (e.g. `modules/home/display-transition.nix`) imported by
+both hyprland.nix and idle.nix, delete the mini, re-run the
+`tools/monitor-fallback.nix` harness + `checks.docking-ux` as the V2 gate.
+Cost: a focused refactor of safety-critical code — deliberately NOT done as
+hygiene drive-by; deserves its own iteration.
+
 ### 149. `[watch]` Waybar's exec-once workaround may be defending against nothing post-linger
 
 Spun out of #147 (shipped 2026-07-17) so its loose thread survives the entry: