Files view: widen the change-details modal again and keep the legend on one row

- modal max-width 900px -> 1100px
- the legend's swatch and label were separate flex children, so a line break
  could split them and the three entries wrapped; each pair is now one
  `.hex-legend-item` (nowrap, no shrink) and the legend itself is
  `flex-wrap: nowrap` with `overflow-x: auto`, so it stays on a single row
- Node test: the modal test now checks the path header and that the legend
  follows the views as three grouped items
- SW cache simtrace-analyser-v70 (cosmetic, no version bump)

frontend/index.html

@@ -190,9 +190,10 @@ body { font: 14px/1.5 system-ui, sans-serif; background: var(--bg); color: var(-
 .file-op-card { color: var(--warn); }
 .file-op .file-op-diff { margin-left: auto; background: none; border: none; color: var(--accent); cursor: pointer; font-size: 12px; padding: 0 2px; flex: 0 0 auto; text-decoration: underline; }
 .file-op .file-op-diff:hover { color: var(--warn); }
-.file-diff-modal { max-width: 900px; }
+.file-diff-modal { max-width: 1100px; }
 .file-diff-body { max-height: 60vh; overflow-y: auto; margin-bottom: 16px; }
-.hex-legend { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--text-muted); margin-top: 10px; flex-wrap: wrap; }
+.hex-legend { display: flex; align-items: center; gap: 14px; font-size: 11px; color: var(--text-muted); margin-top: 10px; flex-wrap: nowrap; overflow-x: auto; }
+.hex-legend-item { display: inline-flex; align-items: center; gap: 4px; white-space: nowrap; flex: 0 0 auto; }
 .hex-summary { font-size: 12px; color: var(--text-muted); margin-bottom: 10px; }
 .hex-pair { display: flex; gap: 16px; flex-wrap: wrap; }
 .hex-pair > div { flex: 1 1 320px; min-width: 0; }
@@ -2253,9 +2254,9 @@ function renderFileDiff(image) {
             <div><h4>${t('After')}</h4>${hexImageHtml(image, 'after')}</div>
         </div>
         <div class="hex-legend">
-            <span class="hex-cell hex-changed">aa</span> ${t('changed')}
+            <span class="hex-legend-item"><span class="hex-cell hex-changed">aa</span> ${t('changed')}</span>
-            <span class="hex-cell hex-new">aa</span> ${t('newly observed')}
+            <span class="hex-legend-item"><span class="hex-cell hex-new">aa</span> ${t('newly observed')}</span>
-            <span class="hex-cell hex-unknown">--</span> ${t('never observed')}
+            <span class="hex-legend-item"><span class="hex-cell hex-unknown">--</span> ${t('never observed')}</span>
         </div>` +
         (image.image_truncated ? `<p class="hex-note">${t('The image is frozen (size cap reached) — later changes are not tracked.')}</p>` : '');
 }

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'simtrace-analyser-v69';
+const CACHE = 'simtrace-analyser-v70';
 
 const PRECACHE = [
     'index.html',

frontend/tests/comprion.test.js

@@ -466,6 +466,7 @@ eval(
 test('Change details modal: header, summary, legend and both views', () => {
 	renderFileDiff({
 		name: 'EF_ICCID',
+		path: 'MF/EF_ICCID (2FE2)',
 		op: 'READ BINARY',
 		record: null,
 		n_records: null,
@@ -478,7 +479,7 @@ test('Change details modal: header, summary, legend and both views', () => {
 		image_truncated: false,
 	});
 	const sub = el('file-diff-sub').textContent;
-	assert.match(sub, /EF_ICCID — READ BINARY/);
+	assert.match(sub, /MF\/EF_ICCID \(2FE2\) — READ BINARY/);
 	assert.match(sub, /#12/);
 	const body = el('file-diff-body').innerHTML;
 	assert.match(body, /2 bytes changed, 4 bytes newly observed/);
@@ -488,6 +489,9 @@ test('Change details modal: header, summary, legend and both views', () => {
 	assert.match(body, /Before/);
 	assert.match(body, /After/);
 	assert.equal((body.match(/class="hex-view"/g) || []).length, 2);
+	// The legend sits below the two views, each swatch bound to its label.
+	assert.ok(body.indexOf('hex-legend') > body.lastIndexOf('hex-view'));
+	assert.equal((body.match(/class="hex-legend-item"/g) || []).length, 3);
 	// The record header variant and the frozen-image note.
 	renderFileDiff({
 		name: 'EF_IMSI', op: 'READ RECORD', record: 2, n_records: 5, index: 40,