Use NotificationBits in Idol

[mkeeter]

This is mostly mechanical, with one logical change: I removed the timer from medusa-seq-server, because it wasn't doing anything.

Requires oxidecomputer/idolatry#69 and staged on top of #2232

[Copilot]

Pull Request Overview

This PR updates the NotificationHandler trait implementations across the codebase to use the new NotificationBits type instead of raw u32 values. The change provides type safety and better APIs for notification handling.

• Replaces raw u32 notification bits with userlib::NotificationBits type
• Updates notification bit checking to use new type-safe methods like is_timer_set() and is_set_unconditional()
• Removes unused timer functionality from medusa-seq-server

Reviewed Changes

Copilot reviewed 54 out of 55 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
Multiple task/drv files	Update handle_notification method signatures to use NotificationBits
sys/userlib/src/lib.rs	Add new methods to NotificationBits type for convenient bit checking
drv/medusa-seq-server/src/main.rs	Remove timer-related code that wasn't being used
task/host-sp-comms/src/main.rs	Mix of new API usage and raw bits access for timer handling
Cargo.toml	Update idolatry dependencies to use feature branch

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[cbiffle]

Looks good!

[cbiffle]

This is technically a functionality change, since it looks like I missed this code when adding the timer checks. But I think the result is correct.

[mkeeter]

IIRC you intentionally skipped it because I was also messing with stuff in #2228 😄