chore: release v0.18.0

[wld-walletkit-bot]

🤖 New release

• walletkit-db: 0.17.1 -> 0.18.0
• walletkit-core: 0.17.1 -> 0.18.0 (⚠ API breaking changes)
• walletkit: 0.17.1 -> 0.18.0 (✓ API compatible changes)

⚠ walletkit-core breaking changes

--- failure constructible_struct_adds_field: externally-constructible struct adds field ---

Description:
A pub struct constructible with a struct literal has a new pub field. Existing struct literals must be updated to include the new field.
        ref: https://doc.rust-lang.org/reference/expressions/struct-expr.html
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/constructible_struct_adds_field.ron

Failed in:
  field CredentialRecord.genesis_issued_at in /tmp/.tmpeP462J/walletkit/walletkit-core/src/storage/types.rs:56
  field CredentialRecord.genesis_issued_at in /tmp/.tmpeP462J/walletkit/walletkit-core/src/storage/types.rs:56

Changelog

walletkit

0.18.0 - 2026-05-15

Other

• add credential pre-flight check against proof requests (#404)

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This PR was generated with release-plz.

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Note

Low Risk
This PR only bumps crate versions and updates the changelog/lockfile; functional code changes are not included in the diff.

Overview
Bumps the workspace and internal crates (walletkit-core, walletkit-db, walletkit, walletkit-cli, and uniffi-bindgen) from 0.17.1 to 0.18.0, updating Cargo.toml and Cargo.lock accordingly.

Updates walletkit/CHANGELOG.md with the 0.18.0 release entry (noting the credential pre-flight check addition).

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