Merge main into the fixture branch

Keeps both halves of the Cargo.toml conflict: the reference_scenarios bench from
this branch and the dev profile from main.

tests/density_fallback_warning.rs

@@ -0,0 +1,65 @@
+//! The recipe's density fallback is reported, not silent.
+//!
+//! [`recipes::default_density`] returns NRLMSISE-00 inside the measured space weather
+//! record and Harris-Priester outside it. That is a real change of physics, so it is
+//! logged at warning level. This lives in its own integration test because installing a
+//! logger is process-wide and each test file is its own binary, so nothing else is
+//! disturbed by it.
+//!
+//! What the resolved force list says is covered by unit tests in `recipes`; this covers
+//! only that the warning reaches a logger, which those cannot see.
+
+// There is no fallback to report without NRLMSISE-00 in the build, so the whole file
+// compiles away rather than leaving an unused logger behind.
+#![cfg(feature = "msis")]
+
+use astrokit::prelude::*;
+use log::{Metadata, Record};
+use std::sync::{Mutex, OnceLock};
+
+static LINES: OnceLock<Mutex<Vec<String>>> = OnceLock::new();
+
+struct Collect;
+
+impl log::Log for Collect {
+    fn enabled(&self, _: &Metadata) -> bool {
+        true
+    }
+    fn log(&self, record: &Record) {
+        LINES
+            .get_or_init(Default::default)
+            .lock()
+            .expect("the collector is not poisoned")
+            .push(format!("{} {}", record.level(), record.args()));
+    }
+    fn flush(&self) {}
+}
+
+#[test]
+fn test_falling_back_to_the_fixed_profile_is_logged() {
+    log::set_boxed_logger(Box::new(Collect)).expect("no other logger in this binary");
+    log::set_max_level(log::LevelFilter::Trace);
+
+    // Inside the record: the measured model, and nothing to report.
+    let covered = Epoch::from_gregorian_utc_hms(2026, 1, 1, 0, 0, 0);
+    let _ = Regime::LowEarth.forces(Fidelity::Balanced, covered);
+    assert!(
+        LINES
+            .get_or_init(Default::default)
+            .lock()
+            .unwrap()
+            .is_empty(),
+        "an epoch inside the record should say nothing"
+    );
+
+    // Far enough ahead to stay outside it however fresh the embedded drivers become.
+    let distant = Epoch::from_gregorian_utc_hms(2100, 1, 1, 0, 0, 0);
+    let _ = Regime::LowEarth.forces(Fidelity::Balanced, distant);
+
+    let lines = LINES.get_or_init(Default::default).lock().unwrap().clone();
+    assert_eq!(lines.len(), 1, "exactly one warning expected: {lines:?}");
+    assert!(lines[0].starts_with("WARN"), "{}", lines[0]);
+    // It has to name both models, or it does not tell the reader what changed.
+    assert!(lines[0].contains("NRLMSISE-00"), "{}", lines[0]);
+    assert!(lines[0].contains("Harris-Priester"), "{}", lines[0]);
+}