fix: also pin proptest <1.7 for MSRV 1.81 compat

proptest 1.7+ requires rustc 1.84, breaking MSRV. Pin to <1.7.
Verified: cargo test passes on both stable and rustc 1.81.

Author: jonwiggins

CHANGELOG.md

@@ -9,8 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
-- Pin `tempfile` dev-dependency to `<3.20` to avoid transitive `getrandom 0.4`
-  which requires `edition2024` (Rust 1.85+), breaking the MSRV of 1.81
+- Pin `tempfile` dev-dependency to `<3.20` and `proptest` to `<1.7` to avoid
+  transitive dependencies requiring Rust 1.84+/1.85+, breaking the MSRV of 1.81
 
 ### Improved
 

Cargo.lock

@@ -45,7 +45,8 @@ tokio = { version = "1", features = ["io-util"], optional = true }
 [dev-dependencies]
 criterion = { version = "0.5", features = ["html_reports"] }
 pretty_assertions = "1"
-proptest = "1"
+# Pin proptest to 1.6.x — 1.7+ requires Rust 1.84+, breaking MSRV 1.81
+proptest = ">=1,<1.7"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 # Pin tempfile <3.20 to avoid getrandom 0.4 which requires edition2024 (Rust 1.85+),