chore: prepare v1.0.1 release

[berisher]

Summary

• bump the project version to 1.0.1 across the Rust package, Python package, and lockfile metadata
• update the public docs to stop advertising the old 0.1.0 pre-release state
• align the developer release instructions with the current tagged GitHub release workflow

Changes

• set version = "1.0.1" in Cargo.toml
• update the editable package version in Cargo.lock to 1.0.1
• set version = "1.0.1" in pyproject.toml
• update the editable package entry in uv.lock to 1.0.1
• change the README current-version section from 0.1.0 (pre-release) to 1.0.1
• replace the stale v0.x.0 release example in DEVELOPING.md with a generic vX.Y.Z flow and note that the GitHub workflow now builds binaries, uploads checksums, and publishes attestations

How to validate

• git diff --check
• cargo test