Nudge running Hunk sessions to pick up new theme colors (#13518)

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

test/cli

@@ -550,6 +550,33 @@ TMUX_LOG="$PI_TMPDIR/tmux.log" PATH="$FAKE_BIN:$ROOT/bin:$PATH" HOME="$PI_TMPDIR
 grep -q 'set-environment -g COLORFGBG 0;15' "$PI_TMPDIR/tmux.log" || fail "tmux sync reads mode from colors.toml"
 pass "tmux sync reads mode from colors.toml"
 
+cat >"$FAKE_BIN/pgrep" <<'EOF'
+#!/bin/bash
+[[ -n $HUNK_RUNNING ]]
+EOF
+chmod +x "$FAKE_BIN/pgrep"
+
+cat >"$FAKE_BIN/pkill" <<'EOF'
+#!/bin/bash
+echo "$*" >>"${PKILL_LOG:-/dev/null}"
+EOF
+chmod +x "$FAKE_BIN/pkill"
+
+cat >"$FAKE_BIN/sleep" <<'EOF'
+#!/bin/bash
+exit 0
+EOF
+chmod +x "$FAKE_BIN/sleep"
+
+HUNK_RUNNING=1 PKILL_LOG="$PI_TMPDIR/pkill.log" PATH="$FAKE_BIN:$ROOT/bin:$PATH" HOME="$PI_TMPDIR" "$ROOT/bin/omarchy-theme-set-hunk"
+[[ $(grep -c -- '-WINCH -x hunk' "$PI_TMPDIR/pkill.log") == "2" ]] || fail "hunk sync signals running hunk sessions"
+pass "hunk sync signals running hunk sessions"
+
+PKILL_LOG="$PI_TMPDIR/pkill-idle.log" PATH="$FAKE_BIN:$ROOT/bin:$PATH" HOME="$PI_TMPDIR" "$ROOT/bin/omarchy-theme-set-hunk"
+[[ ! -e $PI_TMPDIR/pkill-idle.log ]] || fail "hunk sync skips signaling without running hunk"
+pass "hunk sync skips signaling without running hunk"
+rm -f "$FAKE_BIN/pgrep" "$FAKE_BIN/pkill" "$FAKE_BIN/sleep"
+
 cat >"$FAKE_BIN/gsettings" <<'EOF'
 #!/bin/bash
 echo "$*" >>"${GSETTINGS_LOG:-/dev/null}"