refactor(#107): theme-state.json → state.json, theme-sync → state-sync

The machine flake's git-tracked settings file is system state, not
"theme" only — rename it to state.json. CLI becomes nomarchy-state-sync
with a nomarchy-theme-sync symlink for scripts and muscle memory.

Eval (mkFlake, doctor, lifecycle) still accepts theme-state.json; the
next write migrates to state.json and removes the legacy file.
Documented in MIGRATION.md; drop the CLI alias after release notes.

modules/home/waybar.nix

@@ -1,7 +1,7 @@
 # Waybar — two-tier theming:
 #
 #  1. Default: structure, fonts, geometry AND palette baked from
-#     theme-state.json (colors as GTK named colors, @define-color).
+#     state.json (colors as GTK named colors, @define-color).
 #
 #  2. Whole-swap: themes with their own visual identity ship
 #     <themesDir>/<slug>/waybar.css (and optionally waybar.jsonc) which
@@ -35,7 +35,7 @@ let
   # Waybar supervisor — exec-once has no restart, so a crashed bar used to
   # leave the session bar-less until relogin (seen on hardware: a theme
   # switch crashed waybar mid-reload). Respawns on ANY exit — a plain
-  # `pkill -x waybar` is now a clean restart, which nomarchy-theme-sync
+  # `pkill -x waybar` is now a clean restart, which nomarchy-state-sync
   # uses instead of the crash-prone in-place SIGUSR2 reload when it sees
   # this supervisor running. Crash-loop guard: 5 exits within 10s of
   # their start → give up with a critical notification instead of
@@ -377,7 +377,7 @@ let
   };
 
   generatedStyle = ''
-    /* Palette baked from theme-state.json */
+    /* Palette baked from state.json */
     ${colorDefs}
 
     /* NB: this `*` reset reaches the SNI tray menus Waybar hosts too
@@ -522,7 +522,7 @@ in
     # on a warm relogin — it started before the socket was up, exited, landed
     # in `failed`, and was never retried, so the bar vanished. exec-once only
     # fires once Hyprland is up, dodging the race; theme switches reload the
-    # running bar via SIGUSR2 (nomarchy-theme-sync). No uwsm here to manage the
+    # running bar via SIGUSR2 (nomarchy-state-sync). No uwsm here to manage the
     # session target, so we don't depend on its lifecycle.
     systemd.enable = false;