fix(notifications): cap toast height so a long body can't push its close off-screen (#2138)

A balloon reporting a long run/launch error (stack trace, build output) grew
taller than the window: the body had no height limit, so the whole toast
overflowed and its dismiss button and actions scrolled out of reach. Cap the
balloon at the window height and let the body scroll inside it. Fixes #2137.

src/ui/Feedback.module.css

@@ -116,6 +116,8 @@
   display: flex;
   gap: 10px;
   width: 340px;
+  /* Never grow past the window: the close button must stay reachable. */
+  max-height: calc(100vh - 48px);
   padding: 14px 34px 14px 14px;
   background: var(--bg-popup);
   border: 1px solid var(--border-popup);
@@ -166,6 +168,10 @@
 .toastBody {
   color: var(--fg-secondary);
   overflow-wrap: anywhere;
+  /* A huge message (stack trace, build output) scrolls inside the balloon instead
+     of growing past the window and pushing the close button off-screen. */
+  max-height: 40vh;
+  overflow: auto;
   -webkit-user-select: text;
   user-select: text;
 }