Improve SKU catalog hygiene and BOM accuracy

- refresh_sku_catalog.py: add --discover to report API SKUs missing from
  catalog, filtered to already-curated serviceCategory values. Auto-runs
  at end of --validate and --refresh so gaps surface on every maintenance
  pass. First run found 162 missing SKUs (Blackwell GPUs, X12 Ax compute,
  VMware reserved tiers, WebLogic-on-OKE, Analytics/OIC BYOL).
- oci_bom_gen.py: fix Cost % column being blank. Back-fill was gated on
  formula detection but data rows write raw numbers, so the predicate
  never matched. Now tracks data_item_rows explicitly.
- .gitea/workflows/sku-catalog-refresh.yaml: monthly automation (1st at
  09:00 UTC). Auto-refresh prices → push branch + open PR; detect new
  SKUs → open issue with labels. Gated on secrets.GITEA_TOKEN.
- kb/pricing/oci-sku-catalog.yaml: add B95714 / B95715 (Autonomous ATP
  Dedicated ECPU, LI + BYOL) — canonical SKUs for ADB-D pricing.
- kb/services/compute.yaml: add X12 family (VM.Standard4.Ax.Flex,
  BM.Standard4.Ax.120), E6.Ax and A4.Ax variants. Verified against
  docs.oracle.com computeshapes.htm. Bump last_verified + changelog.
- templates/bom-spec.yaml: document 730 hrs/month convention as default
  (= real annual billing / 12; 744 overstates by 1.92% on 12-month TCO).
- Makefile: new 'make sku-discover' target.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

kb/services/compute.yaml

@@ -1,8 +1,11 @@
 ---
-last_verified: 2026-03-14
+last_verified: 2026-04-24
 service: OCI Compute
 category: compute
 oci_color: "#4F7B6E"
+changelog:
+  - date: "2026-04-24"
+    change: "Added missing shapes surfaced by discover+WebFetch: VM/BM.Standard.E6.Ax, VM/BM.Standard.A4.Ax, and full X12 family (VM.Standard4.Ax.Flex 39 OCPU / 360 GB, BM.Standard4.Ax.120 latest-gen bare metal). Verified against docs.oracle.com/en-us/iaas/Content/Compute/References/computeshapes.htm."
 ---
 
 what: Virtual machines and bare metal instances. Flexible shapes allow custom
@@ -42,6 +45,24 @@ shape_families:
     max_ocpu: 18
     memory_per_ocpu_gb: "1-64 GB per OCPU"
     use_for: "High-frequency trading, HPC"
+  - name: VM.Standard.E6.Ax.Flex
+    processor: "AMD EPYC (Ampere-branded E6 variant)"
+    max_ocpu: 94
+    max_memory_gb: 712
+    network_gbps: 99
+    use_for: "E6 Ampere-variant general purpose"
+  - name: VM.Standard.A4.Ax.Flex
+    processor: "Arm (A4 Ampere-branded variant)"
+    max_ocpu: 45
+    max_memory_gb: 720
+    network_gbps: 100
+    use_for: "A4 Ampere-variant Arm workloads"
+  - name: VM.Standard4.Ax.Flex
+    processor: "AMD EPYC (X12 Ampere-branded)"
+    max_ocpu: 39
+    max_memory_gb: 360
+    network_gbps: 99
+    use_for: "X12-generation general purpose (latest)"
   - name: BM.Standard.E5
     processor: "AMD EPYC 9J14 (Genoa)"
     ocpus: 192
@@ -50,6 +71,30 @@ shape_families:
     processor: "AMD EPYC 9J45 (Turin)"
     ocpus: 256
     use_for: "Bare metal latest generation"
+  - name: BM.Standard.E6.Ax.192
+    processor: "AMD EPYC (E6 Ampere-branded variant)"
+    ocpus: 192
+    max_memory_gb: 1536
+    network_gbps: 200
+    use_for: "Bare metal E6 Ampere-variant"
+  - name: BM.Standard.A4.48
+    processor: "Arm (A4)"
+    ocpus: 48
+    max_memory_gb: 768
+    network_gbps: 100
+    use_for: "Bare metal A4 Arm general purpose"
+  - name: BM.Standard.A4.Ax.48
+    processor: "Arm (A4 Ampere-branded variant)"
+    ocpus: 48
+    max_memory_gb: 768
+    network_gbps: 100
+    use_for: "Bare metal A4 Ampere-variant Arm"
+  - name: BM.Standard4.Ax.120
+    processor: "AMD EPYC (X12 Ampere-branded)"
+    ocpus: 120
+    max_memory_gb: 1152
+    network_gbps: 200
+    use_for: "Bare metal X12 latest generation"
   - name: VM.GPU.A10.1
     processor: "NVIDIA A10"
     gpu_count: 1