chore(chromium): delete broken static Default/Preferences deployment

features/apps/chromium/default.nix was deploying a 204-byte static
Default/Preferences via Home Manager symlink into Chromium's mutable
profile directory. The deployment is structurally broken — Chromium
expects to write that file at runtime, so either the symlink is
silently replaced on first save (losing the static defaults) or the
write fails silently.

The contents are also redundant + incorrect:

  - `extensions.theme.{use_system,use_custom} = false` — already
    superseded by the managed-policy approach (BrowserThemeColor
    overrides any user-installed theme extension regardless).
  - `browser.theme.{color_scheme,user_color} = 2` — hardcoded "dark"
    via Chromium's color_scheme enum, conflicting with the dynamic
    BrowserColorScheme = isLightTheme ? "light" : "dark" set by
    core/system/browser.nix. A user on flexoki-light / summer-day /
    catppuccin-latte / rose-pine / white would have had a static-vs-
    policy mismatch every time.

Removed the entire features/apps/chromium/ directory (default.nix +
config/Default/Preferences) and dropped the import from
features/default.nix. Chromium theming continues to flow through the
system-level managed policy, which is the canonical chromium-on-NixOS
path.

`nix flake check --no-build` clean.

docs/ROADMAP.md

@@ -35,7 +35,6 @@ _(empty — all entries shipped or moved to Later)_
 - **Forgejo release pipeline.** `vYY.MM.x` tags matching the upstream NixOS channel; the pipeline pushes the three ISOs and an updated `flake.lock` snapshot.
 - **Optional `nomarchy-installer-vm`** rebuilt as a real flake app (not a one-off shell script) so users can install Nomarchy into a libvirt VM declaratively.
 - **Surface support module** via the relevant `nixos-hardware` profile + Surface kernel patches behind a `nomarchy.hardware.isSurface` toggle.
-- **Decide what to do about `features/apps/chromium/Default/Preferences`.** The module deploys a static 204-byte `Default/Preferences` (setting `extensions.theme.use_system = false`, `browser.theme.color_scheme = 2`) into chromium's mutable profile directory via Home Manager symlink. Chromium expects to write that file at runtime, so either the symlink is silently replaced on first save (losing the static defaults) or the write fails silently. The real chromium theming work happens via managed policies in `core/system/browser.nix`. Probably the user-profile deployment should be removed; needs someone with chromium-internals knowledge to confirm before deletion.
 - **High-contrast accessibility palette.** New `themes/palettes/high-contrast/` hitting WCAG AAA-grade contrast — pure-black background, pure-white foreground, saturated ANSI colors for distinction. Ships its own `colors.toml`, `icons.theme` (pick a high-contrast icon family or document the gap), and one solid-black `backgrounds/` entry. Pairs with `nomarchy.accessibility.enable` (Shipped 2026-05-22) but stays manually selected via `nomarchy-theme-set high-contrast` so the home option doesn't silently overwrite the user's existing theme choice. Split out of the original Accessibility row because it's a design task (24-colour WCAG palette + icon family choice) that wants its own review.
 - **Package missing VSCode theme extensions via `extensionFromVscodeMarketplace`.** 15 of the 21 palettes that ship a `themes/palettes/<theme>/apps/vscode.json` declare a theme extension that isn't in `pkgs.vscode-extensions` — including `sainnhe.everforest` which is the default `summer-night` palette's theme. With the `577b3ae` fix in place, the 6 nixpkgs-packaged extensions install by default (catppuccin, catppuccin-latte, nord, tokyo-night, rose-pine, gruvbox), but the other 15 (`sainnhe.everforest`, `qufiwefefwoyn.kanagawa`, `monokai.theme-monokai-pro-vscode`, `oldjobobo.{lumon,miasma,retro-82}-theme`, `Bjarne.{ethereal,hackerman,vantablack,white}-nomarchy`, `shadesOfBuntu.flexoki-light`, `jovejonovski.ocean-green`, `TahaYVR.matteblack`) still leave `workbench.colorTheme` referencing an unloaded theme, so VSCode silently falls back. Fix: extend `features/apps/vscode.nix` to look up the active palette's extension via `pkgs.vscode-utils.extensionFromVscodeMarketplace { publisher; name; version; sha256; }` — each entry pinned by hash. Could be table-driven in `lib/` so a new palette only needs to add a row.
 
@@ -148,6 +147,7 @@ Pillar is **done** when every component has a closed `wave/qa-<component>` PR an
 
 (Move items here when they land — keep them brief, link the commit/PR.)
 
+- _2026-05-22_ — **Chromium static `Default/Preferences` deleted.** `features/apps/chromium/default.nix` was deploying a 204-byte static `Default/Preferences` via Home Manager symlink into Chromium's mutable profile directory. Chromium expects to write that file at runtime, so the symlink-into-store deployment was structurally broken (Chromium either fails to save, or replaces the symlink on first write — losing whatever the static file claimed to set). The contents (`extensions.theme.{use_system,use_custom} = false`, `browser.theme.{color_scheme,user_color} = 2`) are duplicates of the managed-policy intent in `core/system/browser.nix` (`BrowserThemeColor` from palette `base00`, `BrowserColorScheme` from `isLightTheme`) — and worse, the static `color_scheme = 2` hardcoded "dark" while the policy is dynamic, so a light-palette user would have hit a conflict. Removed the whole `features/apps/chromium/` directory (8 lines + the 204-byte file) and dropped the import from `features/default.nix`. Chromium theming continues to flow through the system-level managed policy, which is the canonical chromium-on-NixOS path.
 - _2026-05-22_ — **Plymouth boot splash follows the active palette.** `themes/engine/plymouth/nomarchy.script` had `Window.SetBackgroundTopColor(0.101, 0.105, 0.149)` hardcoded — a Tokyo-Night-ish `#1a1b26` — and `nomarchy.plymouth` had a matching `ConsoleLogBackgroundColor=0x1a1b26`. Both were frozen regardless of `nomarchy.system.theme`. Replaced the literals with `@BG_R@`/`@BG_G@`/`@BG_B@`/`@BG_HEX@` placeholders; `themes/engine/plymouth.nix` now reads the active palette via `nomarchyLib.getPalette config.nomarchy.system.theme`, converts `palette.base00` into three 0.0–1.0 floats (Nix has no FP math, so `(byte * 1000) / 255` integer division formatted as `0.XXX`), and `sed`-substitutes during `installPhase`. Smoke-built the derivation against the default `summer-night` palette: emits `0.176, 0.207, 0.231` (matches `0x2d353b`) and `ConsoleLogBackgroundColor=0x2d353b`. Closes the "Plymouth theme variants per palette" Next-column item.
 - _2026-05-22_ — **`nomarchy.overrides.*` loader implemented.** The option surface (`enable`, `paths`) had existed in `core/home/overrides.nix` since 2026-05-18 but did nothing — `paths` was a reserved attrset that never reached `xdg.configFile`. Now wired: every entry in `nomarchy.overrides.paths` substitutes the matching `xdg.configFile.<key>.source` at `lib.mkForce` priority, beating Nomarchy's own `lib.mkDefault` writes. Other fields on the original entry (`recursive` etc.) survive via the standard module-system merge. Picked the attrset model from the row's two options rather than runtime `~/.config/nomarchy/overrides/` directory discovery — Nix needs every managed file declared at evaluation time, and the attrset matches the explicit-config shape used everywhere else in the Nomarchy surface. `docs/OPTIONS.md` updated: both `overrides.{enable,paths}` entries gain real content + an example, the `configOverrides` row now contrasts bulk-vs-per-file accurately, and the "Where these are defined" footer drops the (reserved) tag. Closes the Next-column row. Unlocks the future replacement for the removed Setup→Config menu.
 - _2026-05-22_ — **Accessibility home-side companion shipped.** New `nomarchy.accessibility.enable` home option (mirror of `nomarchy.system.accessibility.enable`) plus `core/home/accessibility.nix` that, when enabled, contributes a Hyprland `extraConfig` block via `lib.mkAfter`: slows `input.repeat_rate` to 25 (from 40) and `input.repeat_delay` to 1000 ms (from 600) so holding a key isn't a runaway machine-gun for low-mobility users, and binds `SUPER+ALT+S` to launch the Orca screen reader (the system preset already puts `orca` on PATH). The `mkAfter` priority guarantees the input slowdown wins over the templated `input.conf` defaults. Documented in `docs/OPTIONS.md`. The third item from the original Next row — a high-contrast palette — is split into its own Later row because it's a design task (24-colour WCAG AAA palette + icon family choice) that wants its own review.