Fix 30 KB errors: ExaCS storage 3-10x wrong, ECPU transition, IOPS limits, missing shapes

Cross-referenced all 70+ KB files against official Oracle docs. Critical fixes:
- ExaCS: storage was flash cache not usable disk (76.8→190.8 TB QR), added X11M, removed X10M
- ADB-S: OCPU→ECPU migration, 26ai as default, cross-region RTO 15→10 min
- Compute: E5 max 94→126, A2 80→78, added E6/A4/BM shapes, 11 GPU shapes
- Storage: Higher Perf IOPS 35K→50K, UHP 450K→300K, File Storage 25K→50K
- DBCS: E5.Flex max 94→64, storage 80→150 TB, added 26ai
- Networking: FastConnect +400 Gbps, NSG max 120 rules

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

kb/services/networking.yaml

@@ -22,6 +22,7 @@ components:
     recommendation: "Prefer NSGs (Network Security Groups) for granular control"
   nsg:
     what: "Network Security Group — firewall rules at VNIC level"
+    max_rules: "120 (ingress + egress combined per NSG)"
     recommendation: "Preferred over security lists for micro-segmentation"
   internet_gateway:
     what: "Enables internet access for public subnets"
@@ -45,7 +46,7 @@ components:
 connectivity:
   fastconnect:
     what: "Dedicated private connection to OCI (like AWS Direct Connect)"
-    speeds: ["1 Gbps", "2 Gbps", "5 Gbps", "10 Gbps", "100 Gbps"]
+    speeds: ["1 Gbps", "2 Gbps", "5 Gbps", "10 Gbps", "100 Gbps", "400 Gbps"]
     redundancy: "Always deploy 2 circuits for HA"
     notes: "Partner or co-location model, typical setup takes 2-4 weeks"
   ipsec_vpn: