removing stale cached wgpu pipelines

[nallana]

Note

Medium Risk
Touches wgpu pipeline warmup/caching logic and adds automatic eviction of cached entries, which could affect startup behavior and GPU compatibility if the validation/eviction conditions are wrong.

Overview
During wgpu warmup, cached on-disk pipelines are now validated via wgpu error scopes and any entries that fail creation or a post-create noop pass are treated as incompatible and removed.

warmup_from_disk now accepts a callback to evict the corresponding in-memory cached pipeline key, and shared cleanup logic removes both the .json metadata and .wgsl shader files for the stale entry. (Validation-scope handling is gated to non-wasm32 and is guarded against panics to avoid leaking scopes.)

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Project	Deployment	Actions	Updated (UTC)
runmat	Ready	Preview, Comment, Open in v0	May 6, 2026 3:31pm

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[gneeri]

I would address the cursorbot error about leaked scope, but otherwise, this looks good.