Release 0.9.0

[github-actions]

What's Changed

• chore(deps): bump reqwest from 0.12.23 to 0.12.24 by @dependabot[bot] in chore(deps): bump reqwest from 0.12.23 to 0.12.24 #170
• fix: backup keys are on the secp256k1 curve by @paolodamico in fix: backup keys are on the secp256k1 curve #193
• chore: add localstack token by @paolodamico in chore: add localstack token #195
• Add support for multiple clients by @ketzusaka in Add support for multiple clients #201

New Contributors

• @ketzusaka made their first contribution in Add support for multiple clients #201

Full Changelog: 0.8.5...0.9.0

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Note

Low Risk
Only version and changelog updates; no runtime or application code changes in this PR.

Overview
This PR cuts release 0.9.0 by bumping the workspace and crate versions from 0.8.5 to 0.9.0 in Cargo.toml and Cargo.lock, and adding a 0.9.0 section to CHANGELOG.md that documents what shipped since 0.8.5.

The changelog entry summarizes merged work already on the branch: secp256k1 backup key validation, multi-client support, a reqwest dependency bump, and LocalStack token setup for local dev—not new logic in this diff.

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