Support AWS profiles for deployment (e.g. `agentcore deploy --profile xxx`)

[jesseturner21]

Summary

Customers want to be able to use AWS profiles for deployment, e.g. agentcore deploy --profile xxx.

Problem

• There's no way to select a specific AWS profile when deploying.
• Users working across multiple accounts/profiles can't easily target the intended one for a deployment.

Desired behavior

• Add a --profile option (e.g. agentcore deploy --profile xxx) that uses the specified AWS profile for the deployment.

Environment

• CLI version: 0.22.0
• User agent: AgentCoreCLI/0.22.0 (darwin 25.3.0; node/v24.18.0)
• OS: darwin 25.3.0
• Node: v24.18.0