ludic.ui: emit click reaches on-click, and a select's < steps back

From the user's play: clicking an item in the pack opened nothing, and the wardrobe's picks did
not respond - both are a component whose button says `emit click` (ItemCell, LookCell, ListRow),
answered by its user's on-click. An on-* attribute's name is kept as a browser would have it, so
on-click is on-press (tpl_event), and the emit looked for "click" and found nothing. An emitted
name now goes through the same tpl_event.

And a settings cycler's left arrow did the right one's job: any press let go on a select stepped it
forward. ct_activate_at steps back when it is let go over the select's .ui-prev; Enter and the rest
of the select still step forward.

Goldens ui_emit_click (the mouse and a press both reach on-click; with the toolchain before this,
neither does) and ui_select_arrows (1 -> 0 on <, then 2 on > >; before this, 1 -> 2 on <). The 33
ui examples pass.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.ui/act.ludic

@@ -26,7 +26,7 @@ function act_parse(src: string, err: []string) -> UiAct {
       push(a.exprs, px_cond(r))
     } else if act_keyword(r, "emit") {
       push(a.kinds, A_EMIT)
-      push(a.names, rd_name(r))
+      push(a.names, tpl_event(rd_name(r)))   # `emit click` reaches on-click, which is kept as press
       push(a.exprs, null)
     } else {
       push(a.kinds, A_CALL)

packages/ludic.ui/controls_parts.ludic

@@ -65,3 +65,20 @@ function ct_is_int(s: string, i: int) -> bool {
   }
   return false
 }
+
+# a press let go over a control: on a select's < it steps back, anywhere else on it forward (the <
+# stepped forward too, so a cycler's left arrow did the right one's job)
+function ct_activate_at(ui_st: mut UiState, n: UiNode, x: float, y: float) -> void {
+  if ct_type(n) == "select" and ct_over_part(n, "ui-prev", x, y) {
+    ct_step(ui_st, n, -1)
+    return
+  }
+  ct_activate(ui_st, n)
+}
+function ct_over_part(n: UiNode, cls: string, x: float, y: float) -> bool {
+  for i in 0 .. len(n.children) {
+    let c = n.children[i]
+    if sel_has(c.classes, cls) and x >= c.x and y >= c.y and x < c.x + c.cw and y < c.y + c.ch { return true }
+  }
+  return false
+}

packages/ludic.ui/pointer.ludic

@@ -22,7 +22,7 @@ function fr_pointer(ui_st: mut UiState, root: UiNode) -> void {
   if not i.down and ui_st.in_was_down {
     let was = fr_node(root, ui_st.fr_press_key)
     if was != null { ui_fire(ui_st, was, "up", ui_st.fc_none) }
-    if hit != null and hit.key == ui_st.fr_press_key and hit.enabled { ct_activate(ui_st, hit) }
+    if hit != null and hit.key == ui_st.fr_press_key and hit.enabled { ct_activate_at(ui_st, hit, i.x, i.y) }
     ui_st.fr_press_key = ""
   }
 }