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/hyprland.nix

@@ -1,4 +1,4 @@
-# Hyprland — fully driven by config.nomarchy.theme (theme-state.json).
+# Hyprland — fully driven by config.nomarchy.theme (state.json).
 # Gaps, borders and colors are baked from the JSON at eval time; theme
 # changes arrive via `home-manager switch`.
 { config, lib, pkgs, ... }:
@@ -8,7 +8,7 @@ let
   c = t.colors;
   inherit (config.nomarchy.lib) rgb rgba;
 
-  # nomarchy-theme-sync — the in-flake state writer the keyboard watcher uses
+  # nomarchy-state-sync — the in-flake state writer the keyboard watcher uses
   # to remember per-device layouts (same path night-light's toggle takes).
   sync = lib.getExe config.nomarchy.package;
 
@@ -883,7 +883,7 @@ in
         "awww-daemon"
         # Paint the wallpaper as soon as the session is up (waits for
         # the daemon internally).
-        "nomarchy-theme-sync wallpaper"
+        "nomarchy-state-sync wallpaper"
         # Polkit authentication agent — without one, EVERY pkexec/polkit
         # prompt in the session fails silently (btrfs-assistant-launcher
         # was the discovery case). hyprpolkitagent is Hyprland's own Qt
@@ -903,8 +903,8 @@ in
         ];
 
       # ── Theme-driven look ──────────────────────────────────────────
-      # These flow from theme-state.json and stay at NORMAL priority:
-      # change them with `nomarchy-theme-sync set ui.<key>` (the intended
+      # These flow from state.json and stay at NORMAL priority:
+      # change them with `nomarchy-state-sync set ui.<key>` (the intended
       # path), or lib.mkForce in home.nix to hardcode against the theme.
       # The non-theme knobs around them are lib.mkDefault — override
       # those with a plain home.nix assignment. See docs/OVERRIDES.md.