assistant_tools: Rename `FileToolInput` to `NowToolInput` (#25456)
Nikita Pivkin
created
Renamed the `FileToolInput` structure to `NowToolInput` to better
reflect its purpose, as the tool is related to time-based operations.
Release Notes:
- N/A
Signed-off-by: Nikita Pivkin <nikita.pivkin@smartforce.io>