Opt: Pre-fetch current input method before im-select to reduce one ca…

[cnxiaochun]

The im-select flow has been optimized:

It now pre-fetches and prints the current input method state.

The actual input method switching logic is only executed if the desired input method does not match the current one.

This change effectively reduces the overall call overhead by one on every execution, as the necessary state information is now obtained as a prerequisite step.