Multitenant blueprint updates

[amizer12]

• Remove ProjectionExpression and ExpressionAttributeNames from DynamoDB scan to retrieve all fields instead of frontend-specific subset
• Expand Bedrock IAM policy resources to support cross-region access with wildcard region parameter
• Add inference-profile resource ARN to Bedrock permissions for enhanced model invocation capabilities
• Simplifies token usage handler to return complete item data for more flexible downstream processing

Amazon Bedrock AgentCore Samples Pull Request

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