fix: block-repeat sweep checkbox rendered as a giant blue square

The generic input{width:100%; min-height:...} rule (meant for text fields)
was also catching the raw checkbox, since nothing scoped it down the way
every other checkbox in the app does (.field-toggle, .eng-field). Same fix
as those: width auto, plus a small flex label so it sits inline with its
text instead of centered alone on its own line.

movie_editor/frontend/block_sweep.js

@@ -52,8 +52,8 @@
     sceneRow.append(el("label", "sw-label", "Scene to sweep"), sceneSel);
     container.append(sceneRow);
 
-    const expCb = el("input"); expCb.type = "checkbox";
-    const expLabel = el("label", "sw-hint");
+    const expCb = el("input"); expCb.type = "checkbox"; expCb.style.width = "auto";
+    const expLabel = el("label", "sw-hint sw-check-label");
     expLabel.append(expCb, document.createTextNode(
       " Show experimental config — unvalidated, results will not match any prior sweep 1:1 "
       + "(different checkpoint/steps/sampler port nothing over, see the block-repeat research notes)"));

movie_editor/frontend/styles.css

@@ -2182,6 +2182,8 @@ body.tour-mode { overflow: hidden; }
 .sw-textarea { width: 100%; box-sizing: border-box; font-family: var(--font-mono, monospace);
   font-size: 12px; padding: 8px; border: 1px solid var(--line); border-radius: 8px;
   background: var(--ink-2); color: var(--text); resize: vertical; }
+.sw-check-label { display: flex; align-items: flex-start; gap: 8px; cursor: pointer; }
+.sw-check-label > input[type="checkbox"] { flex: 0 0 auto; min-height: 0; margin-top: 2px; }
 .sw-rows-label { margin: 16px 4px 5px; font-size: 10px; font-weight: 700; letter-spacing: .6px;
   text-transform: uppercase; color: var(--faint); }
 .sw-rows { display: flex; flex-direction: column; border: 1px solid var(--line); border-radius: 10px;