feat(menu): adopt rofi plugins for calc, files, emoji

Replace the hand-rolled calc/files modules with purpose-built rofi modi
(via programs.rofi.plugins) and add an emoji picker — all themed through
the same .rasi as every other modi:

- calc -> rofi-calc: live results as you type via libqalculate directly,
  which also dodges the qalc CLI's "15% of 200" -> rem(15, 1 B) misparse.
  Enter copies; the menu persists to chain calculations. Drops the
  libqalculate (qalc CLI) dependency.
- files -> rofi-file-browser-extended: live directory navigation +
  xdg-open, replacing the flat 50k-cap `fd` dump of $HOME. yazi (SUPER+E)
  stays the power browser; `fd` already ships via shell.nix.
- emoji -> rofi-emoji (new module): glyph picker, copies through the
  plugin's Wayland clipboard adapter. Bound to SUPER+CTRL+E in
  keybinds.nix (so it lands in the SUPER+? cheatsheet too).

rofi 2.0 rebuilds cleanly with all three plugin .so (ABI-matched, same
nixpkgs). README roadmap updated: calc rework marked shipped, with a
follow-up item for the script-based plugins (network/secrets/audio).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -295,8 +295,9 @@ close · `SUPER+1..9` workspaces · `Print` region screenshot.
     `nomarchy-menu` dispatcher: root picker (no args) · `power`
     (lock/logout/suspend/hibernate/reboot/shutdown, SUPER+X) ·
     `theme` (SUPER+T) · `clipboard` (cliphist, SUPER+CTRL+V) · `calc`
-    (qalc, copy/chain) · `files` (fd → xdg-open) · `web` (Google).
-    SUPER+D is `rofi -show drun`.
+    (rofi-calc, live, SUPER+CTRL+C) · `files` (rofi-file-browser, live
+    navigation, SUPER+CTRL+F) · `emoji` (rofi-emoji, SUPER+CTRL+E) ·
+    `web` (Google). SUPER+D is `rofi -show drun`.
   - ✓ shipped modules: `network` (nmtui in `$TERMINAL`) · `bluetooth`
     (blueman-manager) · `capture` (grim/slurp submenu: region/full →
     clipboard/file, saved to `~/Pictures/Screenshots`) · `keybinds` (the
@@ -317,15 +318,26 @@ close · `SUPER+1..9` workspaces · `Print` region screenshot.
     launcher, no second theming pipeline; the dispatcher owns the menu
     structure, so the renderer stays swappable (we moved fuzzel → rofi 2.0
     once mainline gained native Wayland, for its richer theming)
-- **Calculator module rework:** the current `calc` flow
-  (`modules/home/rofi.nix`) is unsatisfying — you commit the expression
-  blind, then the result only appears in the *next* menu's `-mesg` line,
-  and `qalc -t` misparses common phrasings (e.g. `15% of 200` →
-  `rem(15, 1 B)` instead of `30`). Rework toward live results as you type
-  (rofi-calc-style: each keystroke re-evaluates and the answer is the top
-  entry, Enter copies), a more robust qalc invocation, and graceful
-  handling of parse errors. Decide whether to keep the hand-rolled dmenu
-  loop or adopt a dedicated calc mode/plugin.
+- ✓ **Menu modules from rofi plugins:** the old `calc` flow committed the
+  expression blind (result only in the *next* menu's `-mesg`) and `qalc -t`
+  misparsed common phrasings (`15% of 200` → `rem(15, 1 B)`, the natural-
+  language "of" tripping the CLI). Resolved by adopting purpose-built rofi
+  modi (`programs.rofi.plugins`), all themed through the same `.rasi`:
+  - **calc** → **rofi-calc**: live results as you type via libqalculate
+    directly (dodging the qalc-CLI "of" bug), Enter copies, menu persists
+    to chain calculations.
+  - **files** → **rofi-file-browser-extended**: live directory navigation
+    (Backspace to ascend, toggle hidden) opening with xdg-open, replacing
+    the flat `fd` dump of `$HOME`. yazi (SUPER+E) stays the power browser.
+  - **emoji** → **rofi-emoji** (new module, SUPER+CTRL+E): glyph picker,
+    copies via the plugin's Wayland clipboard adapter.
+- **More menu modules from rofi tools:** the script-based counterparts
+  (run via `rofi -dmenu`, like the hand-rolled modules), each a deliberate
+  replacement of an existing flow: **rofi-network-manager** (a keyboard
+  wifi/VPN picker vs today's `nmtui`-in-terminal `network`), **rofi-rbw /
+  rofi-pass** (a secrets module — Bitwarden via rbw, or `pass` — pairs with
+  `keys.nix`), and **rofi-pulse-select** (an audio sink/source switcher).
+  Decide per-module whether it earns replacing the current path.
 - **Theme parity with legacy:** summer-day/night now carry their legacy
   bar layouts as `waybar.jsonc` whole-swaps (adapted: dead legacy script
   modules dropped, Nerd-Fonts-v2 codepoints remapped to FontAwesome/v3,