[UX] Tab completion for commands, aliases, and templates

[jwesleye]

Feature Description

Auto-complete commands, agent aliases, and prompt templates with Tab key.

Problem/Motivation

Hard to remember exact names. Tab completion is expected in modern CLIs.

Proposed Solution

• Tab to complete commands: tem<TAB> → templates
• Tab to complete aliases: my<TAB> → myagent
• Tab to complete templates: /rev<TAB> → /review
• Fuzzy matching for close matches

Benefits

• Faster typing
• Discover features
• Reduce errors
• Standard CLI behavior

Priority

• Critical
• High
• Medium
• Low

[github-actions]

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It will be closed in 14 days if no further activity occurs.

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Thank you for your contributions!

[jwesleye]

Closing as not planned.

Tab completion would require significant terminal integration complexity and isn't essential for the core AWS Strands CLI experience. The help command provides clear guidance on available commands, aliases, and templates.

Keeping the CLI simple and focused on the chat experience itself.