home: centralize theme and make home-manager feature-aware

- add home/theme.nix as the single Silicon Volt palette and pass it to
  home modules via extraSpecialArgs
- drive foot, hyprland, hyprlock, mako, fzf, starship, rofi and the
  herdr picker from that palette; raw config files use @color@ tokens
  substituted at build time
- pass my = config.my into home-manager; add my.pi.enable, my.flakeDir
- gate home/pi.nix on my.pi.enable (enabled on hades)
- route zshconf/hyprconf aliases and FLAKE_CONFIG through my.flakeDir
- rename the hyprland monitor option volt.monitors -> hypr.monitors
- fix use_auto_tmux command-substitution bug in zsh/init.zsh
- track home/nvim/config/lazy-lock.json for reproducible plugins
- document theming and toggles in the README

home/foot.nix

@@ -1,4 +1,10 @@
-{ pkgs, inputs, ... }:
+{
+  pkgs,
+  lib,
+  inputs,
+  theme,
+  ...
+}:
 
 let
   herdrPkg =
@@ -13,7 +19,35 @@ let
     else
       (pkgs.herdr or null);
 
-  herdrPicker = pkgs.writeShellScriptBin "herdr-picker" (builtins.readFile ./scripts/herdr-picker.sh);
+  # Inject the shared palette into the picker script (see home/theme.nix).
+  herdrPicker = pkgs.writeShellScriptBin "herdr-picker" (
+    lib.replaceStrings
+      [
+        "@bg@"
+        "@glass@"
+        "@fg@"
+        "@fgBright@"
+        "@muted@"
+        "@volt@"
+        "@voltLight@"
+        "@coral@"
+        "@blue@"
+        "@surface@"
+      ]
+      [
+        theme.colors.bgPrimary
+        theme.colors.glassBg
+        theme.colors.textSecondary
+        theme.colors.textPrimary
+        theme.colors.textMuted
+        theme.colors.accentVolt
+        theme.colors.accentVoltLight
+        theme.colors.accentCoral
+        theme.colors.accentBlue
+        theme.colors.surfaceVariant
+      ]
+      (builtins.readFile ./scripts/herdr-picker.sh)
+  );
 in
 {
   home.packages = (if herdrPkg != null then [ herdrPkg ] else [ ]) ++ [
@@ -47,41 +81,38 @@ in
         hide-when-typing = "yes";
       };
 
+      # Silicon Volt palette, sourced from home/theme.nix.
       colors-dark = {
-        # Silicon Volt palette (matches home/hypr theme + mako):
-        # bgPrimary #131313, bgSecondary #0e0e0e, glassBg #1c1b1b,
-        # textPrimary #ffffff, textSecondary #e5e2e1, textMuted #adaaaa,
-        # accents: volt #cffc00, coral #ff7a59, blue #00bfff
         alpha = 0.92;
-        background = "131313";
-        foreground = "e5e2e1";
+        background = theme.bare.bgPrimary;
+        foreground = theme.bare.textSecondary;
 
         # Cursor text and cursor (background) colors
-        cursor = "0e0e0e cffc00";
+        cursor = "${theme.bare.bgSecondary} ${theme.bare.accentVolt}";
 
-        regular0 = "0e0e0e"; # bgSecondary
-        regular1 = "ff7a59"; # accentCoral
-        regular2 = "cffc00"; # accentVolt (green)
-        regular3 = "e3ff66"; # accentVoltLight (yellow)
-        regular4 = "00bfff"; # accentBlue
-        regular5 = "c6c6c7"; # Neutral Gray (magenta)
-        regular6 = "66d9ff"; # Light Cyan
-        regular7 = "e5e2e1"; # textSecondary
+        regular0 = theme.bare.bgSecondary;
+        regular1 = theme.bare.accentCoral;
+        regular2 = theme.bare.accentVolt;
+        regular3 = theme.bare.accentVoltLight;
+        regular4 = theme.bare.accentBlue;
+        regular5 = theme.bare.neutralGray;
+        regular6 = theme.bare.lightCyan;
+        regular7 = theme.bare.textSecondary;
 
         # Bright Colors
-        bright0 = "2a2929"; # surfaceVariant
-        bright1 = "ff9a82"; # Bright Coral
-        bright2 = "dfff66"; # Bright Lime
-        bright3 = "f0ff8c"; # Bright Volt
-        bright4 = "66d9ff"; # Bright Blue
-        bright5 = "e0e0e1"; # Bright Gray
-        bright6 = "99e6ff"; # Bright Cyan
-        bright7 = "ffffff"; # textPrimary
+        bright0 = theme.bare.surfaceVariant;
+        bright1 = theme.bare.brightCoral;
+        bright2 = theme.bare.brightLime;
+        bright3 = theme.bare.brightVolt;
+        bright4 = theme.bare.lightCyan;
+        bright5 = theme.bare.brightGray;
+        bright6 = theme.bare.brightCyan;
+        bright7 = theme.bare.textPrimary;
 
         # Selection & URLs - volt lime selection like the site
-        selection-foreground = "0e0e0e";
-        selection-background = "cffc00";
-        urls = "00bfff";
+        selection-foreground = theme.bare.bgSecondary;
+        selection-background = theme.bare.accentVolt;
+        urls = theme.bare.accentBlue;
       };
     };
   };