fix(frontend): left-align the sidebar nav items on the mobile drawer

The nav buttons defaulted to centered for the desktop icon rail and were
flipped back by `[data-state="expanded"]`. That attribute tracks the
desktop open state, while the mobile drawer runs off `openMobile`, so on
a phone the labels rendered but the override never matched: 新建对话 and
我的报告 floated mid-drawer while every other row sat flush left.

Left alignment is the base layer now, correct for both the drawer and the
expanded desktop sidebar, and centering moved into the >=768px collapsed
block beside the rest of the rail rules. That was the only top-level
`[data-state=...]` selector left in the stylesheet.

personal-report-entry asserted `justify-content: center` on the report
button, which is the defect itself; the value is updated and the rest of
that assertion stands.

BUG-438.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0155nFCgCHtoA7jhSDGmZmMu

frontend/tests/personal-report-entry.test.ts

@@ -211,9 +211,12 @@ test("entry is global in the sidebar and absent from the active session header",
   assert.match(pageSource, /onOpenReports=\{\(\) => router\.push\("\/reports"\)\}/);
   assert.doesNotMatch(pageSource, /window\.location\.assign\("\/reports"\)/);
   assert.doesNotMatch(pageSource, /GeneratePersonalReportButton|reportEntryVisible|reportEvidenceState/);
+  // Was `justify-content: center`, which is what put 我的报告 in the middle of
+  // the mobile drawer (BUG-438). The base layer is left-aligned now; centering
+  // moved into the >=768px collapsed rail, locked by sidebar-contract.
   assert.match(
     globalStyles,
-    /\.report-nav-button \{[^}]*display: flex;[^}]*align-items: center;[^}]*justify-content: center;/,
+    /\.report-nav-button \{[^}]*display: flex;[^}]*align-items: center;[^}]*justify-content: flex-start;/,
   );
 });
 

frontend/tests/sidebar-contract.test.ts

@@ -10,6 +10,32 @@ const globalStyles = readProjectFile("src/app/globals.css");
 
 const cssBlock = (selector: string) => cssDeclarations(selector, globalStyles);
 
+/** The base-layer rule only — media-query copies of a selector are indented. */
+const topLevelRule = (selector: string) => {
+  const escaped = selector.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
+  const hit = globalStyles.match(new RegExp(`^${escaped}\\s*\\{([^}]*)\\}`, "m"));
+  assert.ok(hit, `no base-layer rule for ${selector}`);
+  return hit[1];
+};
+
+test("sidebar nav items read left-aligned everywhere; centering is the desktop rail only", () => {
+  // `data-state` tracks the DESKTOP open state, so it cannot decide layout on
+  // the mobile drawer — that drawer is always expanded no matter what the
+  // desktop rail is doing. Centering as the base layer, flipped back by a
+  // `[data-state="expanded"]` override, left 新建对话 / 我的报告 floating in
+  // the middle of the drawer on phones while every other row sat flush left.
+  for (const selector of [".new-chat", ".report-nav-button"]) {
+    assert.match(topLevelRule(selector), /justify-content:\s*flex-start/);
+    assert.doesNotMatch(topLevelRule(selector), /justify-content:\s*center/);
+  }
+  assert.doesNotMatch(globalStyles, /\[data-state="expanded"\][^{]*\.(?:new-chat|report-nav-button)/);
+  // The rail lives at >=768px, beside the other collapsed-state rules.
+  assert.match(
+    globalStyles,
+    /@media\s*\(min-width:\s*768px\)[\s\S]*\[data-state="collapsed"\]\s+\.new-chat,\s*\[data-state="collapsed"\]\s+\.report-nav-button\s*\{[^}]*justify-content:\s*center/,
+  );
+});
+
 test("provides the generic composable sidebar primitive", () => {
   assert.equal(existsSync(projectFile("src/components/ui/sidebar.tsx")), true);
 });