feat: extend commands coverage & add request wait for approval

[MatteoManzoni]

Summary

Completes the request lifecycle by adding the missing operations from the AWS TEAM API:

• team reject <id> — approver rejects a pending request
• team revoke <id> — requester or approver revokes an active session (approved/scheduled/in progress)
• team cancel <id> — requester cancels their own pending request
• team pending — lists requests awaiting the current user's approval (uses the requestByApproverAndStatus GSI)
• team request --wait — blocks until the request reaches a terminal state, with configurable timeout (--wait-timeout, default 600s)

--wait behavior

Designed for scripting and wrapper tools. Polls the request status every 5 seconds, prints progress to stderr, and exits with:

Exit code	Meaning
0	approved / in progress
1	rejected, cancelled, expired, or error
2	timeout

When stdout is not a TTY (piped), outputs the final request state as JSON. Tokens are refreshed automatically during long waits.