feat: surface BMC collection errors in parse-errors panel and event log

When Inspur component.log sections return {"error":"...","code":N} instead
of hardware data, the parser now:
- stores them in AnalysisResult.CollectionErrors (new model field)
- mirrors each one into result.Events with Source="BMC/<section>"
  so the chart viewer event table shows the specific BMC module
- feeds them into /api/parse-errors as bmc_collection_error entries

UI adds a collapsible "Collection diagnostics" panel below the chart
iframe (outside /chart) that appears when /api/parse-errors returns
any items; resets on data clear.

Affected sections in this dump: HDD (1458), PCIe Devices (1458),
Network Adapters (1458), Disk Backplane.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/static/css/style.css

@@ -933,3 +933,73 @@ code {
         grid-template-columns: 1fr;
     }
 }
+
+/* ── Parse / collection errors panel ───────────────────────────────────── */
+.parse-errors-section {
+    margin: 0 auto;
+    max-width: 1200px;
+    padding: 0 1.5rem 1.5rem;
+}
+
+.parse-errors-header {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    padding: .55rem .75rem;
+    background: var(--warn-bg);
+    border: 1px solid #f0e0c0;
+    border-radius: 6px 6px 0 0;
+    cursor: pointer;
+    user-select: none;
+    font-weight: 600;
+    font-size: .85rem;
+    color: var(--warn-fg);
+}
+
+.parse-errors-toggle {
+    font-size: .75rem;
+    opacity: .7;
+}
+
+.parse-errors-body {
+    border: 1px solid #f0e0c0;
+    border-top: none;
+    border-radius: 0 0 6px 6px;
+    overflow-x: auto;
+}
+
+.parse-errors-table {
+    width: 100%;
+    border-collapse: collapse;
+    font-size: .82rem;
+}
+
+.parse-errors-table th {
+    background: var(--surface-3);
+    padding: .4rem .65rem;
+    text-align: left;
+    font-weight: 600;
+    color: var(--muted);
+    border-bottom: 1px solid var(--border);
+    white-space: nowrap;
+}
+
+.parse-errors-table td {
+    padding: .38rem .65rem;
+    border-bottom: 1px solid var(--border-lite);
+    vertical-align: top;
+}
+
+.parse-errors-table tr:last-child td {
+    border-bottom: none;
+}
+
+.parse-error-row.parse-error-error td:first-child {
+    color: var(--crit-fg);
+    font-weight: 600;
+}
+
+.parse-error-row.parse-error-warning td:first-child {
+    color: #7a5200;
+    font-weight: 600;
+}