Update Rust crate iddqd to 0.4.0

[oxide-renovate]

This PR contains the following updates:

Package	Type	Update	Change
iddqd	workspace.dependencies	minor	0.3.18 → 0.4.0

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Release Notes

oxidecomputer/iddqd (iddqd)

v0.4.0

Compare Source

Changed

• The internal implementation for item storage has been changed to use a linear slot-based buffer, resulting in 2-3x performance improvements for most workloads.
• The maps now have a limit of u32::MAX (4 294 967 295) elements at any given time. This limit is very unlikely to be reached in practice.

Fixed

• All mutation methods for IdHashMap and IdOrdMap are now panic-safe, in the sense that a panic in user code will not corrupt the map. This does not currently extend to BiHashMap and TriHashMap

Added

• Many more unit and property-based tests covering various kinds of pathological user implementations. We now have high confidence that arbitraily buggy user implementations (as long as they're in safe Rust) will not result in undefined behavior.

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This PR has been generated by Mend Renovate.