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/nic_mellanox_test.go

@@ -55,7 +55,7 @@ func TestEnrichPCIeWithMellanox_mstflint(t *testing.T) {
 	}
 	netIfacesByBDF = func(string) []string { return nil }
 
-	vendorID := mellanoxVendorID
+	vendorID := MellanoxVendorID
 	bdf := "0000:18:00.0"
 	manufacturer := "Mellanox Technologies"
 	devs := []schema.HardwarePCIeDevice{{
@@ -99,7 +99,7 @@ func TestEnrichPCIeWithMellanox_fallbackEthtool(t *testing.T) {
 		return "driver: mlx5_core\nfirmware-version: 28.40.1000\n", nil
 	}
 
-	vendorID := mellanoxVendorID
+	vendorID := MellanoxVendorID
 	bdf := "0000:18:00.0"
 	manufacturer := "NVIDIA Networking"
 	devs := []schema.HardwarePCIeDevice{{