Fix boundary gaps found in GPT-4.1 cross-review

Three issues from the mandatory IAM cross-review (BLOCK/FIX):

1. Add KMS statement — PaymentsDashboard DynamoDB table and
   payments-dashboard CloudWatch log groups use CMKs. Without
   kms:Decrypt + kms:GenerateDataKey in the boundary, those Lambda
   calls fail at the KMS layer at runtime. Scoped to account keys only.

2. Add table/*/index/* to DynamoDB resource — dynamodb:Query on a GSI
   requires the index ARN; covering only table/* silently denied GSI
   queries at the boundary.

3. Fix EC2 ENI statement — remove AssignPrivateIpAddresses /
   UnassignPrivateIpAddresses (EFA-only, not part of Lambda ENI
   lifecycle); add DescribeSubnets + DescribeSecurityGroups + DescribeVpcs
   which are required by the Lambda service during VPC attachment and are
   present in AWSLambdaVPCAccessExecutionRole.

4. Add SES configuration-set/* resource — ses:SendRawEmail requires
   permission on the configuration set if one is passed at send time.

Refs: INFRA-103

oidc-deploy-roles.yaml

@@ -118,19 +118,23 @@ Resources:
             Resource: "*"
 
           # ── VPC / ENI management (payments-dashboard VPC functions) ────────
-          # ec2:Describe* are required even for non-VPC Lambdas as the ENI
-          # lifecycle actions need them.
+          # Matches AWSLambdaVPCAccessExecutionRole exactly.
+          # AssignPrivateIpAddresses / UnassignPrivateIpAddresses are for EFA
+          # and secondary IPs — not part of the Lambda ENI lifecycle — omitted.
           - Sid: Ec2Eni
             Effect: Allow
             Action:
               - ec2:CreateNetworkInterface
               - ec2:DescribeNetworkInterfaces
               - ec2:DeleteNetworkInterface
-              - ec2:AssignPrivateIpAddresses
-              - ec2:UnassignPrivateIpAddresses
+              - ec2:DescribeSubnets
+              - ec2:DescribeSecurityGroups
+              - ec2:DescribeVpcs
             Resource: "*"
 
           # ── DynamoDB (afterhours, payments, meal-order, front-integrations) ─
+          # Table/* covers base-table operations; table/*/index/* is required for
+          # Query/Scan on Global Secondary Indexes.
           - Sid: DynamoDB
             Effect: Allow
             Action:
@@ -146,6 +150,7 @@ Resources:
               - dynamodb:ConditionCheckItem
             Resource:
               - !Sub "arn:aws:dynamodb:us-east-1:${AWS::AccountId}:table/*"
+              - !Sub "arn:aws:dynamodb:us-east-1:${AWS::AccountId}:table/*/index/*"
 
           # ── S3 (payments-dashboard read, meal-order-manager CRUD) ──────────
           - Sid: S3
@@ -216,6 +221,25 @@ Resources:
               - ses:SendRawEmail
             Resource:
               - !Sub "arn:aws:ses:us-east-1:${AWS::AccountId}:identity/*"
+              - !Sub "arn:aws:ses:us-east-1:${AWS::AccountId}:configuration-set/*"
+
+          # ── KMS (CMK-encrypted resources) ─────────────────────────────────
+          # Required for Lambda functions that read/write CMK-encrypted AWS
+          # resources.  Verified live state:
+          #   - PaymentsDashboard DynamoDB table: CMK key/0b660af3 (KMS:ENABLED)
+          #   - payments-dashboard CloudWatch log groups: CMK key/b748750c
+          # Secrets Manager + SQS queues in these stacks use AWS-managed keys
+          # (aws/secretsmanager, aws/sqs) which do not require explicit kms:*
+          # actions in the execution role policy.  The CMK keys are scoped to
+          # this account to prevent cross-account KMS calls.
+          - Sid: KMS
+            Effect: Allow
+            Action:
+              - kms:Decrypt
+              - kms:GenerateDataKey
+              - kms:DescribeKey
+            Resource:
+              - !Sub "arn:aws:kms:us-east-1:${AWS::AccountId}:key/*"
 
   # ---------------------------------------------------------------------------
   # Shared CloudFormation execution role (SAM stacks)