Trim launcher overhead for terminals and web apps (#13423)

omarchy-launch-webapp asked xdg-settings for the default browser with
BROWSER still set to omarchy-launch-browser, which sends it down a
slower path to the same answer: ~105ms instead of ~30ms on every web app
launch. Unset it, as omarchy-launch-browser already does.

omarchy-cmd-terminal-cwd found the focused terminal's shell with pgrep,
which scans all of /proc on every new terminal. Read the terminal's
child lists from /proc instead, keeping the newest child as before.

Web app wrapper overhead drops from ~111ms to ~34ms, and a new terminal
appears in ~77ms instead of ~90ms.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

bin/omarchy-cmd-terminal-cwd

@@ -11,7 +11,16 @@ if [[ -S $kitty_socket ]]; then
   cwd=$(kitten @ --to "unix:$kitty_socket" ls --match "state:focused" 2>/dev/null |
     jq -r '.[].tabs[].windows[].cwd // empty')
 else
-  shell_pid=$(pgrep -P "$terminal_pid" | tail -n1)
+  # The newest child, as pgrep -P | tail -n1 found it, read from the kernel's
+  # child lists: pgrep scans all of /proc on every new terminal.
+  shell_pid=""
+  for children_file in /proc/"$terminal_pid"/task/*/children; do
+    [[ -r $children_file ]] || continue
+    read -ra children <"$children_file" || true
+    for child in "${children[@]}"; do
+      (( child > ${shell_pid:-0} )) && shell_pid=$child
+    done
+  done
 
   if [[ -n $shell_pid ]]; then
     cwd=$(readlink -f "/proc/$shell_pid/cwd" 2>/dev/null)

bin/omarchy-launch-webapp

@@ -3,7 +3,9 @@
 # omarchy:summary=Launch a URL as a web app in the default supported browser
 # omarchy:args=<url>
 
-browser=$(xdg-settings get default-web-browser)
+# The session sets BROWSER to omarchy-launch-browser, which sends xdg-settings
+# down a slower path (~100ms against ~30ms) to the same answer.
+browser=$(env -u BROWSER xdg-settings get default-web-browser)
 
 case $browser in
 google-chrome* | brave* | microsoft-edge* | opera* | vivaldi* | helium*) ;;

test/shell.d/terminal-cwd-test.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+set -euo pipefail
+
+source "$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)/base-test.sh"
+
+test_tmp=$(mktemp -d)
+stub_bin="$test_tmp/bin"
+work_dir="$test_tmp/project dir"
+mkdir -p "$stub_bin" "$work_dir"
+
+# A stand-in terminal whose newest child is a shell sitting in work_dir. The
+# trailing ":" keeps bash from exec'ing sleep, so the child stays a shell.
+bash -c '(cd "$1" && bash -c "sleep 30; :") & wait' _ "$work_dir" &
+terminal_pid=$!
+
+# Children first: killing a parent reparents its children out of reach.
+kill_tree() {
+  local child
+  for child in $(cat /proc/"$1"/task/*/children 2>/dev/null); do
+    kill_tree "$child"
+  done
+  kill "$1" 2>/dev/null || true
+}
+trap 'kill_tree "$terminal_pid"; wait "$terminal_pid" 2>/dev/null || true; rm -rf "$test_tmp"' EXIT
+
+for _ in $(seq 50); do
+  [[ -n $(cat /proc/"$terminal_pid"/task/*/children 2>/dev/null) ]] && break
+  sleep 0.05
+done
+
+cat >"$stub_bin/hyprctl" <<'SH'
+#!/bin/bash
+[[ -n ${ACTIVE_PID:-} ]] && printf 'Window 1 -> terminal:\n\tpid: %s\n' "$ACTIVE_PID"
+exit 0
+SH
+chmod +x "$stub_bin/hyprctl"
+
+cwd=$(ACTIVE_PID="$terminal_pid" PATH="$stub_bin:$PATH" XDG_RUNTIME_DIR="$test_tmp" "$ROOT/bin/omarchy-cmd-terminal-cwd")
+[[ $cwd == "$work_dir" ]] || fail "a new terminal opens in the focused terminal's shell directory" "got: $cwd"
+pass "a new terminal opens in the focused terminal's shell directory"
+
+output=$(PATH="$stub_bin:$PATH" XDG_RUNTIME_DIR="$test_tmp" HOME="$test_tmp" "$ROOT/bin/omarchy-cmd-terminal-cwd" 2>&1)
+[[ $output == "$test_tmp" ]] || fail "with no focused terminal the new one opens in HOME" "got: $output"
+pass "with no focused terminal the new one opens in HOME, quietly"