feat: exposes rpc queries on xscheduler

[amimart]

Purpose of Changes and their Description

The PR brings RPC queries allowing to inspect the x/scheduler module state:

• Tasks: Retrieve all the tasks in the state, scheduled or not;
• Task: Retrieve the details of a task given its id;
• ScheduledTasks: Retrieve the currently scheduled tasks for a specific type, not the one created with no execution scheduled;
• Handlers: Retrieve the currently registered task handlers, in their execution order;

⚠️ The Handlers query is marked as unsafe as it is not based on any state but on the currently registered task handlers.

There are some pagination and filtering options on the Tasks and ScheduledTasks queries.

For each RPC query a related CLI query command has been added.

Are these changes tested and documented?

• If tested, please describe how. If not, why tests are not needed.
• If documented, please describe where. If not, describe why docs are not needed.
• Added to Unreleased section of CHANGELOG.md?

Still Left Todo

• Tests
• CLI

[github-actions]

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Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	⏩ skipped	Oct 21, 2025, 3:20 PM