feat(capture): screen recording — menu start, bar-click stop (item 12)

nomarchy-record owns the lifecycle: start prefers wl-screenrec (VAAPI
hardware encode) and falls back to wf-recorder if it dies at startup
(the no-VAAPI case), stop SIGINTs so the file finalizes cleanly, and
status feeds a self-gating Waybar ⏺ REC (alert red) whose click is
the one stop surface — signal 8 pokes make it appear/vanish
instantly. Capture gains Record region/screen (+ audio variants) and
self-swaps to '■ Stop recording' while one runs. Parity: both summer
whole-swap bars carry the same module. Recordings land in
~/Videos/Recordings with the screenshot timestamp naming (deviation
from 'next to Screenshots': an .mp4 in Pictures felt wrong).

V1: rendered bar config + CSS asserted, summer jsonc parse, recorder
dry-run state machine correct (idle/active/usage exits), both
recorders in home-path. Real capture needs a session → V3 queued
(incl. the VAAPI-vs-fallback check on the AMD box).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

modules/home/recording.nix

@@ -0,0 +1,99 @@
+# Screen recording (menu › Tools › Capture). One helper owns the whole
+# lifecycle: `start` launches wl-screenrec (VAAPI hardware encode) and
+# falls back to wf-recorder (software x264) if it dies on the spot —
+# e.g. no usable VAAPI device; `status` feeds the self-gating Waybar
+# indicator (waybar.nix, signal 8), whose click is the ONE stop surface
+# (`stop` SIGINTs the recorder so it finalizes the file cleanly). State
+# is a runtime pidfile — nothing persists across sessions.
+{ config, lib, pkgs, ... }:
+
+lib.mkIf config.nomarchy.rofi.enable {
+  home.packages = [
+    pkgs.wl-screenrec
+    pkgs.wf-recorder
+
+    (pkgs.writeShellScriptBin "nomarchy-record" ''
+      run="''${XDG_RUNTIME_DIR:-/run/user/$(id -u)}"
+      pidfile="$run/nomarchy-record.pid"
+      filefile="$run/nomarchy-record.file"
+
+      alive() { [ -f "$pidfile" ] && kill -0 "$(cat "$pidfile")" 2>/dev/null; }
+      poke_bar() { pkill -RTMIN+8 waybar 2>/dev/null || true; }
+
+      case "''${1:-}" in
+        start)
+          if alive; then
+            notify-send "Screen recording" "Already recording — stop it via the ⏺ in the bar."
+            exit 1
+          fi
+          target="''${2:-screen}"; audio="''${3:-}"
+          geo=""
+          if [ "$target" = region ]; then
+            geo=$(slurp) || exit 0   # Esc in slurp = cancel, silently
+          fi
+          dir="$HOME/Videos/Recordings"
+          mkdir -p "$dir"
+          file="$dir/$(date +%Y%m%d-%H%M%S).mp4"
+
+          launch() {  # launch <recorder> -> 0 if it survived startup
+            case "$1" in
+              wl-screenrec)
+                setsid wl-screenrec ''${geo:+-g "$geo"} \
+                  ''${audio:+--audio} -f "$file" >/dev/null 2>&1 & ;;
+              wf-recorder)
+                setsid wf-recorder ''${geo:+-g "$geo"} \
+                  ''${audio:+-a} -f "$file" >/dev/null 2>&1 & ;;
+            esac
+            echo $! > "$pidfile"
+            sleep 0.7
+            alive
+          }
+
+          started=""
+          if command -v wl-screenrec >/dev/null 2>&1 && launch wl-screenrec; then
+            started=wl-screenrec
+          elif command -v wf-recorder >/dev/null 2>&1 && launch wf-recorder; then
+            started=wf-recorder   # software fallback (no VAAPI device)
+          fi
+          if [ -z "$started" ]; then
+            rm -f "$pidfile"
+            notify-send "Screen recording" "Recorder failed to start (no wl-screenrec/wf-recorder able to run)."
+            exit 1
+          fi
+          printf '%s' "$file" > "$filefile"
+          poke_bar
+          notify-send "Screen recording" "Recording ($started)''${audio:+ with audio} — click the ⏺ in the bar to stop." ;;
+
+        stop)
+          if ! alive; then
+            rm -f "$pidfile" "$filefile"; poke_bar
+            notify-send "Screen recording" "No recording is running."
+            exit 0
+          fi
+          pid=$(cat "$pidfile")
+          kill -INT "$pid" 2>/dev/null   # graceful: both recorders finalize on INT
+          for _ in $(seq 1 50); do kill -0 "$pid" 2>/dev/null || break; sleep 0.1; done
+          kill -0 "$pid" 2>/dev/null && kill "$pid" 2>/dev/null
+          file=$(cat "$filefile" 2>/dev/null || echo "?")
+          rm -f "$pidfile" "$filefile"
+          poke_bar
+          notify-send "Screen recording saved" "$file" ;;
+
+        active)
+          alive ;;
+
+        status)
+          # Waybar JSON while recording; nothing => module hidden.
+          if alive; then
+            file=$(cat "$filefile" 2>/dev/null || echo "")
+            printf '{"text":"⏺ REC","class":"recording","tooltip":"Recording to %s — click to stop"}\n' "''${file##*/}"
+          fi
+          exit 0 ;;
+
+        *)
+          echo "usage: nomarchy-record start [region|screen] [audio] | stop | active | status" >&2
+          exit 2 ;;
+      esac
+    '')
+  ];
+}