Track PCIe AER correctable errors; fix GPU status key routing

Add nvidia-aer-correctable and pcie-aer-correctable patterns to catch
"bus correctable error" events seen in SEL (Critical Interrupt / offset 7).
Both patterns carry severity "warning" — correctable errors are
hardware-recovered and should not flag a card as failed.

Fix kmsg_watcher routing: GPU-category events were keyed as pcie:<BDF>
but the UI queries for pcie:gpu: prefix. Split the switch so "gpu" →
pcie:gpu:<BDF> and "pcie" → pcie:<BDF>. This applies to both
flushWindow (SAT-window path) and flushImmediate (always-on path).

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

audit/internal/platform/error_patterns.go

@@ -38,6 +38,15 @@ var HardwareErrorPatterns = []ErrorPattern{
 		Category: "gpu",
 		Severity: "warning",
 	},
+	// PCIe AER correctable from the NVIDIA driver — "bus correctable error" in SEL.
+	// Severity is warning (not critical): correctable errors are hardware-recovered.
+	{
+		Name:     "nvidia-aer-correctable",
+		Re:       mustPat(`(?i)nvidia\s+([\da-f]{4}:[\da-f]{2}:[\da-f]{2}\.\d).*AER.*[Cc]orrect`),
+		Category: "gpu",
+		Severity: "warning",
+		BDFGroup: 1,
+	},
 	{
 		Name:     "nvidia-aer",
 		Re:       mustPat(`(?i)nvidia\s+([\da-f]{4}:[\da-f]{2}:[\da-f]{2}\.\d).*AER`),
@@ -54,6 +63,15 @@ var HardwareErrorPatterns = []ErrorPattern{
 	},
 
 	// ── PCIe AER (generic) ──────────────────────────────────────────────────────
+	// PCIe AER correctable from the root port — captures the reported device BDF
+	// (second BDF in "pcieport X: AER: Correctable error received: Y").
+	{
+		Name:     "pcie-aer-correctable",
+		Re:       mustPat(`(?i)pcieport.*AER:.*[Cc]orrect.*:\s*([\da-f]{4}:[\da-f]{2}:[\da-f]{2}\.\d)`),
+		Category: "pcie",
+		Severity: "warning",
+		BDFGroup: 1,
+	},
 	{
 		Name:     "pcie-aer",
 		Re:       mustPat(`(?i)pcieport\s+([\da-f]{4}:[\da-f]{2}:[\da-f]{2}\.\d).*AER`),

audit/internal/webui/kmsg_watcher.go

@@ -165,7 +165,9 @@ func (w *kmsgWatcher) flushWindow(window *kmsgWindow) {
 		for _, id := range evt.ids {
 			var key string
 			switch evt.category {
-			case "gpu", "pcie":
+			case "gpu":
+				key = "pcie:gpu:" + normalizeBDF(id)
+			case "pcie":
 				key = "pcie:" + normalizeBDF(id)
 			case "storage":
 				key = "storage:" + id
@@ -218,7 +220,9 @@ func (w *kmsgWatcher) flushImmediate(evt kmsgEvent) {
 	for _, id := range evt.ids {
 		var key string
 		switch evt.category {
-		case "gpu", "pcie":
+		case "gpu":
+			key = "pcie:gpu:" + normalizeBDF(id)
+		case "pcie":
 			key = "pcie:" + normalizeBDF(id)
 		case "storage":
 			key = "storage:" + id