feat(scripts): extend nomarchy-welcome into a guided wizard

- Added nomarchy.panelPosition option and state persistence.
- Updated Waybar to respect the panelPosition setting.
- Refactored nomarchy-welcome to use state.json instead of a flag file.
- Added prompts for theme, font, panel position, and starter home.nix generation.
- Updated documentation and roadmap.

docs/ROADMAP.md

@@ -26,7 +26,6 @@ Guardrails (apply when adding anything):
 - **Accessibility — home-side companion.** Hyprland-side bits the system preset can't reach: slower `input.repeat_rate` / `repeat_delay` defaults, `SUPER+ALT+S` keybinding to launch Orca, and a high-contrast palette under `themes/palettes/`. Gated on a new `nomarchy.accessibility.enable` mirror of the system option.
 - **Gaming — Hyprland window rule.** Companion to the gaming preset: a Hyprland `windowrulev2 = fullscreen, class:^(steam_app_).*$` (or similar) so games launched from Steam grab the whole screen. Lives in `core/home/config/nomarchy/default/hypr/` and gates on a new `nomarchy.gaming.enable` mirror.
 - **Gaming — declarative flathub remote.** `services.flatpak.enable` doesn't ship a declarative remote API in nixpkgs. Either add the `flatpak-managed-install` overlay, write a one-shot systemd unit that runs `flatpak remote-add --if-not-exists flathub …`, or surface the manual step in `nomarchy-welcome`.
-- **First-run welcome wizard.** Extend `nomarchy-welcome` from a one-shot greeter into a guided picker: theme, panel position, monospace font, "what's a sane home.nix to start with?". Runs once, persists "done" in `state.json`.
 - **Plymouth theme variants per palette.** Currently one Plymouth theme; could template per-palette so the boot splash matches the active theme.
 
 ### Later (speculative or research-shaped)
@@ -138,6 +137,7 @@ Nomarchy is moving away from being a "flavor" of Omarchy to its own distinct ide
 
 (Move items here when they land — keep them brief, link the commit/PR.)
 
+- _2026-04-26_ — First-run welcome wizard (`nomarchy-welcome`). Extended from a one-shot greeter into a guided picker for theme, font, and panel position. Added Step 4 to generate a starter `home.nix` if missing. State is now persisted in `state.json` via `.welcome_done`. Added `nomarchy.panelPosition` option to Waybar.
 - _2026-04-26_ — Multi-disk BTRFS support in the installer. Added `installer/disko-btrfs-multi.nix` template and updated `installer/install.sh` to allow selecting multiple drives via `gum choose --no-limit`. Implements BTRFS "single" data + RAID1 metadata across multiple LUKS-encrypted drives.
 - _2026-04-26_ — Distro Branding Phase 2. Updated bootloader entries to use "Nomarchy" as the label. Set ISO volume IDs to `NOMARCHY_INSTALLER` and `NOMARCHY_LIVE`. Fixed branding in Plymouth theme metadata and SDDM metadata.
 - _2026-04-26_ — Distro Branding Phase 1. Renamed `installerIso` to `nomarchy-installer` and `installerIsoGraphical` to `nomarchy-live`. Updated metadata and host configurations. Scrubbed "Omarchy" from Plymouth and installer messages.