chore(deps): update all dependencies including toml 1.0, toml_edit 0.25, jsonschema 0.44

Major version bumps:
- toml 0.9 -> 1.0 (stable release, no API changes for our usage)
- toml_edit 0.24 -> 0.25 (companion to toml 1.0)
- jsonschema 0.37 -> 0.44 (updated validator API)

Removed:
- rand dev-dependency (no direct usage in codebase)

Minor/patch updates via cargo update (~80 crates), including:
- clap 4.5.51 -> 4.5.60
- tokio 1.48 -> 1.50
- serde_json 1.0.145 -> 1.0.149
- regex 1.12.2 -> 1.12.3
- proptest 1.9 -> 1.10
- assert_cmd 2.1.1 -> 2.1.2 (now requires must_use on assert())

Also fixes unused_must_use warnings in crlf_line_endings_test.rs
triggered by assert_cmd 2.1.2 adding #[must_use] to assert().

Author: rvben