test: chromeless + modal-swallow coverage

Adds assertions verifying:
- chromeless=true widget click at top-right reaches widget (no
  phantom close-button intercept).
- top-tier input_block=all modal swallows outside-clicks before
  reaching normal-tier widgets behind it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

init.lua

@@ -550,6 +550,58 @@ function M.run_tests(_ctx)
     T.assert(not panel.point_in_any_panel(sw_p * 0.75, sh_p * 0.5),
         "W.2 point_in_any_panel false when point outside any panel")
     panel._test_reset_all()
+
+    -- ------------------------------------------------------------------
+    -- W.2 #12: chromeless=true suppresses phantom close-button hit-test
+    -- ------------------------------------------------------------------
+    -- Regression: chromeless widgets draw no X close-button but the
+    -- dispatch loop used to hit-test a phantom 26x26 zone at the top-
+    -- right. A click there would close the widget. Verify the click
+    -- now reaches the widget instead.
+    local chrome_clicked = false
+    panel.register("w_chrome", make_widget({
+        title = "ChromelessW",
+        handle_input = function(_ctx, _ev) chrome_clicked = true end,
+    }), { chromeless = true, layout = "center" })
+    panel.open("w_chrome")
+    local b_chrome = panel._test_get_window_bounds("w_chrome")
+    -- Click in the top-right area where the phantom close-button would sit.
+    panel._dispatch_event_for_test({
+        kind = "click", button = "left",
+        x = b_chrome.x + b_chrome.w - 10,
+        y = b_chrome.y + 10,
+    })
+    T.assert(chrome_clicked,
+        "chromeless: top-right click reaches widget (no phantom close-button)")
+    T.assert(panel.is_open("w_chrome"),
+        "chromeless: widget remains open after top-right click")
+    panel._test_reset_all()
+
+    -- ------------------------------------------------------------------
+    -- W.2 #13: top-tier input_block="all" swallows outside-clicks before
+    --          they can reach a normal-tier widget behind the modal.
+    -- ------------------------------------------------------------------
+    local normal_clicked_m = false
+    panel.register("w_norm_m", make_widget({
+        title = "N",
+        handle_input = function(_ctx, _ev) normal_clicked_m = true end,
+    }), { z_tier = "normal", layout = "left-half" })
+    panel.register("w_modal_m", make_widget({
+        title = "M",
+        handle_input = function(_ctx, _ev) end,
+    }), { z_tier = "top", input_block = "all", layout = "right-half" })
+    panel.open("w_norm_m")
+    panel.open("w_modal_m")
+    -- Click in left-half (inside normal's bounds, outside modal's bounds).
+    -- The modal must swallow it before normal can claim it.
+    local sw_mm, sh_mm = panel._test_get_screen_size()
+    panel._dispatch_event_for_test({
+        kind = "click", button = "left",
+        x = sw_mm * 0.25, y = sh_mm * 0.5,
+    })
+    T.assert(not normal_clicked_m,
+        "modal swallow: normal-tier widget does NOT receive click while top-tier all-modal is open")
+    panel._test_reset_all()
 end
 
 return M