feat(cloud): add --wait flag to fixed database and subscription commands

[joshrotenberg]

Summary

Add --wait flag support to Cloud fixed database and fixed subscription operations that return task IDs, building on #191.

Part of #175

Background

Fixed database and subscription operations are asynchronous. With the async_utils module from #191, we can extend --wait functionality to these commands.

Commands to Update

Fixed Database Operations (5 commands)

• cloud fixed-database create - Creating fixed databases
• cloud fixed-database update - Updating fixed databases
• cloud fixed-database delete - Deleting fixed databases
• cloud fixed-database backup - Backup operations
• cloud fixed-database import - Import operations

Fixed Subscription Operations (3 commands)

• cloud fixed-subscription create - Creating fixed subscriptions
• cloud fixed-subscription update - Updating fixed subscriptions
• cloud fixed-subscription delete - Deleting fixed subscriptions

Implementation Notes

1. Update CloudFixedDatabaseCommands and CloudFixedSubscriptionCommands in cli.rs
2. Update handlers in fixed_database.rs and fixed_subscription.rs
3. Use handle_async_response() from async_utils module
4. Note: Fixed operations use different ID formats (subscription_id:database_id)

Example Usage

# Create fixed database and wait
redisctl cloud fixed-database create --subscription-id 123 --file @config.json --wait

# Delete fixed subscription with confirmation
redisctl cloud fixed-subscription delete 456 --yes --wait

Acceptance Criteria

• All 8 commands support --wait flag
• ID parsing works correctly for fixed database format
• Progress indicators and timeouts work
• Backward compatibility maintained