Optimize UI CPU usage

[Gold856]

Description

The first change is to remove dynamically calculated classes from photon-sidebar. On my laptop, this eats about 5% CPU out of 30% when idling. Still trying to hunt down other sources of CPU usage; baseline last year was ~10%.

Meta

Merge checklist:

• Pull Request title is short, imperative summary of proposed changes
• The description documents the what and why
• If this PR changes behavior or adds a feature, user documentation is updated
• If this PR touches photon-serde, all messages have been regenerated and hashes have not changed unexpectedly
• If this PR touches configuration, this is backwards compatible with settings back to v2025.3.2
• If this PR touches pipeline settings or anything related to data exchange, the frontend typing is updated
• If this PR addresses a bug, a regression test for it is added

[samfreund]

Is the goal here to optimize CPU usage on the client or the coprocessor?

[Gold856]

On the client.