Use type-erased facet APIs for persistence callbacks

[fasterthanlime]

Summary

• Replace facet_postcard::to_vec with peek_to_vec(Peek::new(...)) for serialization
• Replace facet_postcard::from_slice with from_slice_into for deserialization
• Update facet to include the new from_slice_into API from Reduce monomorphization and add from_slice_into APIs for msgpack/postcard facet-rs/facet#1932

How it works

The key insight is that while Peek::new and heap_value.materialize() are still generic, they are tiny (just pointer/shape manipulation). The heavy lifting happens in:

• peek_to_vec(peek) - non-generic, compiled once
• from_slice_into(bytes, partial) - non-generic, compiled once

This reduces monomorphization in the persistence callbacks:

• make_encode_record
• make_decode_record
• make_encode_incremental
• make_apply_wal_entry

Test plan

• All 66 picante tests pass

Closes #51

[Copilot]

Pull request overview

This PR reduces monomorphization in picante's persistence layer by replacing generic serialization/deserialization APIs with type-erased alternatives. The key innovation is that while Peek::new and materialize() remain generic (but are tiny operations), the heavy lifting is done by non-generic functions peek_to_vec and from_slice_into that are compiled only once.

Changes:

• Replace facet_postcard::to_vec with peek_to_vec(Peek::new(...)) for serialization
• Replace facet_postcard::from_slice with a multi-step type-erased deserialization flow using from_slice_into
• Update facet dependency from 0.42.0 to 0.43.2 to access new type-erased APIs

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File	Description
crates/picante/src/ingredient/derived.rs	Updated four persistence callback functions (make_encode_record, make_decode_record, make_encode_incremental, make_apply_wal_entry) to use type-erased serialization/deserialization APIs, reducing monomorphization while maintaining functionality
Cargo.lock	Updated facet dependencies from 0.42.0 to 0.43.2, added new transitive dependencies (cobs, corosensei, embedded-io, foldhash, iddqd, object, postcard, thiserror), and updated cranelift and wasmtime dependencies to newer versions

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