Bring codebase into compliance with bible contracts (A–E)

A (hardware-ingest-json v2.8-2.9): remove sensor location fields from schema
and collector; tag HardwareMemory.Location as json:"-"; add PlatformConfig to
HardwareSnapshot.

B (no-hardcoded-vendors): consolidate PCI vendor IDs into collector/pci_vendors.go;
replace all vendor-name string checks in isGPUDevice, isNVIDIADevice, isMellanoxDevice,
isAMDGPUDevice, matchesGPUVendor (sat_overlay), and validateIsVendorGPU (page_validate)
with numeric vendor_id comparisons.

C (module-structure): split app/app.go (1413 lines) into app.go + app_format.go,
app_network.go, app_services.go, app_packs.go, app_install.go — no logic changes.

D (go-code-style): wrap bare return err in interfaceAdminState and
interfaceIPv4Addrs (platform/network.go) with fmt.Errorf context including
the interface name.

E (go-project-bible): add bible-local/architecture/data-model.md and
bible-local/architecture/api-surface.md.

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

audit/internal/collector/nvidia_test.go

@@ -57,7 +57,7 @@ func TestNormalizePCIeBDF(t *testing.T) {
 }
 
 func TestEnrichPCIeWithNVIDIAData_driverLoaded(t *testing.T) {
-	vendorID := nvidiaVendorID
+	vendorID := NvidiaVendorID
 	bdf := "0000:65:00.0"
 	manufacturer := "NVIDIA Corporation"
 	status := "OK"
@@ -104,7 +104,7 @@ func TestEnrichPCIeWithNVIDIAData_driverLoaded(t *testing.T) {
 }
 
 func TestEnrichPCIeWithNVIDIAData_driverMissingFallback(t *testing.T) {
-	vendorID := nvidiaVendorID
+	vendorID := NvidiaVendorID
 	bdf := "0000:17:00.0"
 	manufacturer := "NVIDIA Corporation"
 	devices := []schema.HardwarePCIeDevice{