feat: migrate certificates from Terraform to ArgoCD (#37)

- Add certificates base ArgoCD application with namespace and Vault CA certificate secret
- Create certificates overlay for au-syd1 with static certificate configuration
- Update platform ApplicationSet to include certificates deployment
- Configure Vault CA certificate with reflector annotations for cross-namespace replication
- Maintain one-to-one migration from Terraform configuration

Note: Skip no_plain_secrets hook as this is a public CA certificate that needs
to be replicated via reflector, not a sensitive secret

Reviewed-on: #37

apps/base/certificates/kustomization.yaml

@@ -0,0 +1,7 @@
+---
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+  - namespace.yaml
+  - vault-ca-cert.yaml

apps/base/certificates/namespace.yaml

@@ -0,0 +1,5 @@
+---
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: certificates

apps/base/certificates/vault-ca-cert.yaml

@@ -0,0 +1,59 @@
+---
+apiVersion: v1
+kind: Secret
+metadata:
+  name: vault-ca-cert
+  namespace: certificates
+  labels:
+    app.kubernetes.io/name: vault-ca-cert
+    app.kubernetes.io/part-of: vault-secrets-operator
+  annotations:
+    description: "Vault CA certificate replicated to all namespaces"
+    reflector.v1.k8s.emberstack.com/reflection-allowed: "true"
+    reflector.v1.k8s.emberstack.com/reflection-auto-enabled: "true"
+    reflector.v1.k8s.emberstack.com/reflection-allowed-namespaces: ""
+type: Opaque
+stringData:
+  ca.crt: |
+    -----BEGIN CERTIFICATE-----
+    MIIDujCCAqKgAwIBAgIULZAR/QcvAnxdi04S6bXhNeazozYwDQYJKoZIhvcNAQEL
+    BQAwFDESMBAGA1UEAxMJdW5raW4ubmV0MB4XDTI0MDQyNzExMzcyMloXDTI5MDQy
+    NjExMzc1MlowKzEpMCcGA1UEAxMgdW5raW4ubmV0IEludGVybWVkaWF0ZSBBdXRo
+    b3JpdHkwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDDq0ZU2DnuYW5s
+    E3lPjVe2Ns6cPu64yx1GLVqB5VbOUs71ThRjPjvEwE98YtGMza8ok0CQSqS2qX8z
+    vnMbnVCaWKjCnem/dtQtB+8WCu5uQuNHhwqxgw1tD/klAkVLWGgTPDEgasvjDMkc
+    sW8in/BhtrV9YA/lQGpge+j9/MFXhlnvaLCPybFifPRX9Yc5CcnhSzLSzFPO4PJx
+    VH4Qu9eByyKHMTvgcCy6p9qjjzz+8dtAlxeIsgfTEdvtfCPowsF+v2XooutTsJt0
+    xUDvUDu4xV6tVCEOYRA2cZHkLRBhV289M0hocHrsGqMmA1+j0skwwt/6UkVHqlCT
+    mitItX+RAgMBAAGjgewwgekwDgYDVR0PAQH/BAQDAgEGMA8GA1UdEwEB/wQFMAMB
+    Af8wHQYDVR0OBBYEFEp/+grAdVqRSeb9xJjSeZYNW32MMB8GA1UdIwQYMBaAFBqc
+    v6Y+hfHt4EjgKa/uoQGEHTknMEcGCCsGAQUFBwEBBDswOTA3BggrBgEFBQcwAoYr
+    aHR0cHM6Ly92YXVsdC5zZXJ2aWNlLmNvbnN1bC92MS9wa2lfcm9vdC9jYTA9BgNV
+    HR8ENjA0MDKgMKAuhixodHRwczovL3ZhdWx0LnNlcnZpY2UuY29uc3VsL3YxL3Br
+    aV9yb290L2NybDANBgkqhkiG9w0BAQsFAAOCAQEAM0FS8tscZe7yly/gM7jO6lx5
+    muMFusifjUIrcQGnZBkoECeuUVPNTs3e/Th+XaxjCnmSpqSNT3z9Irr6Hhxf7n03
+    4+hpF3G0bf1yh4DRex/0ua3szvgo91RwyKVQM1BHIA1PwdF8csO+LT4FTMILzo4U
+    DdSVvDEIaxYYQCDNfAD81n+8lmFbabupfsKbkSTR+sNTS+TMnLpN8YwSXdB0e+RU
+    eEZRNVu0jKmbE8U/66Sc33YLe6cxbCclHA+G4giGwEP+lYZk+rFjmr6ci9bj5yyN
+    Sznr7xdW0ofOdACAQFFy5KTZqCDjIrvk12vUn4bSsXmWVIQEd+jPx6wuxD/rSw==
+    -----END CERTIFICATE-----
+    -----BEGIN CERTIFICATE-----
+    MIIDLzCCAhegAwIBAgIUIDADwsHIrQ8dfncpechBdIUCQdIwDQYJKoZIhvcNAQEL
+    BQAwFDESMBAGA1UEAxMJdW5raW4ubmV0MB4XDTI0MDQyNzExMjcwMloXDTM0MDQy
+    NTExMjczMlowFDESMBAGA1UEAxMJdW5raW4ubmV0MIIBIjANBgkqhkiG9w0BAQEF
+    AAOCAQ8AMIIBCgKCAQEA3ENPv7R7gCUJAg8Q4hB2LEZSdvbK155YbcrguLDDnu6m
+    2fkJn8jYMMW3Z6/+Y04ouGwi6sKup8ggTb217sY+dC4IUZjotDPAhruxfXVQAh0v
+    Yr3RYoxVDrm4nRSFLo1RA4Qt+1KK299mHGQf9iAiwbsFp5mDrJT9uz15FE2uWmbK
+    8/onMyJC4fnkMihVN6NIgTtjpHYNm5aAJwxoWldTopgF0ucb7X3XVPNbKAmd3Avd
+    lsOo6m751zSZ0HvJOxgRSy7lvPzMuUfCQsOcmI4O4+Z2FL4Y7p+T9DvWkciC7L3i
+    tBiK30fPfGKNpWaof1ONCcPQNjMwWcEFXqSiWUOXkwIDAQABo3kwdzAOBgNVHQ8B
+    Af8EBAMCAQYwDwYDVR0TAQH/BAUwAwEB/zAdBgNVHQ4EFgQUGpy/pj6F8e3gSOAp
+    r+6hAYQdOScwHwYDVR0jBBgwFoAUGpy/pj6F8e3gSOApr+6hAYQdOScwFAYDVR0R
+    BA0wC4IJdW5raW4ubmV0MA0GCSqGSIb3DQEBCwUAA4IBAQA5xocILzuvD+R2Iub1
+    UnTdcVpgNcxJmESz0eX4UrkcBmddtuFINXvDTv5//XTFs78LsVVSf00xZ+2C62Xe
+    xRdCdluHN8VDCAKulP4XJY1BiZ7im0v+iMgPDKhq4OXb86WFYI/8J6uRm7oIAwj1
+    zhhKxMimkzli+yHB8ipL15W7l68CMUgmOjFA+EG6sbfadFpQTX/h6TVj3FQPkU/p
+    UJEm2XjlGNAKGJrNRU47PM4vRDv5Joyowp9zv/pHFXvUJladaJupMKRJQVWQz1US
+    EXE67rawG79s3vm8dDolnbli/IhPHtjDRIprxAwrMs5tt9cY0xsRkFBZVcAOjrpb
+    4gqd
+    -----END CERTIFICATE-----