Topbar: title trim, shorter search, the view selector pinned above the panel (v2.6.3)

- the header title drops its "UICC" prefix — "GSMTAP trace analyser" is enough
- the trace topbar's search input is half its previous width (flex basis
  33.333% -> 16.667%); the session name now ellipsizes instead of wrapping
  the tighter row
- the side-panel view selector moved out of the scrollable side panel into
  the trace topbar: right-aligned over the panel at the panel's width
  (--side-panel-w: 260px, the negative right margin cancelling the topbar's
  16px padding so the edges line up), so it stays visible at all times while
  the panel scrolls
- tests: the topbar/selector position pins (the Files-view wiring test and
  style.test.js), the shared width variable, the halved search basis and the
  title; 527 Python + 61 Node tests
- README/README_RUS: the selector's new place; PWA_VERSION/pyproject/
  version.py 2.6.3, SW cache simtrace-analyser-v77

frontend/tests/style.test.js

@@ -21,3 +21,29 @@ test('no per-element scrollbar overrides or thin default remain', () => {
 	assert.doesNotMatch(src, /\.side-panel::-webkit-scrollbar/);
 	assert.doesNotMatch(src, /::-webkit-scrollbar \{ width: 6px/);
 });
+
+// ── trace topbar layout ────────────────────────────────────────────────
+
+test('the view selector sits over the side panel at the panel width', () => {
+	// one layout variable keeps the two the same width
+	assert.match(src, /--side-panel-w: 260px;/);
+	assert.match(src, /\.side-panel \{ width: var\(--side-panel-w\);/);
+	assert.match(src, /\.trace-topbar \.side-view-select \{ width: var\(--side-panel-w\); flex: 0 0 auto; margin-left: auto; margin-right: -16px; \}/);
+	// the selector is a topbar control (before the two-column trace area,
+	// which keeps it visible while the panel scrolls)
+	const topbar = src.indexOf('<div class="trace-topbar">');
+	const sel = src.indexOf('id="side-view-select"');
+	const main = src.indexOf('<div class="trace-main">');
+	assert.ok(topbar >= 0 && topbar < sel && sel < main, 'selector in the topbar');
+});
+
+test('the search input is half its previous width', () => {
+	assert.match(src, /\.trace-topbar input \{ flex: 0 1 16\.667%;/);
+	// a long session name ellipsizes rather than wrapping the now tighter row
+	assert.match(src, /\.trace-topbar #session-name-display \{ white-space: nowrap; overflow: hidden; text-overflow: ellipsis; \}/);
+});
+
+test('the header title carries no UICC prefix', () => {
+	assert.match(src, /<div class="header-title"><a href="https:\/\/osmocom\.org\/projects\/baseband\/wiki\/GSMTAP"/);
+	assert.doesNotMatch(src, /class="header-title">UICC/);
+});