fix(clippy): bring source under -D warnings ahead of CI

Prep for the Forgejo CI gate. Adjustments per module are small
and local:

  - test modules get inner `#![allow(clippy::unwrap_used,
    expect_used, panic)]` so the existing assert.expect()
    test idiom keeps working without rewriting every fixture
  - the dead_code field that downstream consumers may still
    want serialised gets an explicit #[allow(dead_code)]
  - manual char/range comparisons fold to the idiomatic forms
    (`['…']`, `(2..=5).contains(&n)`)
  - one snake_case rename in text-readability-score

Also re-bakes module.wasm so the committed artefact matches
the post-fmt source byte-for-byte.

No behaviour change, no test change. cargo fmt --all -- --check
and cargo clippy --all-targets -- -D warnings now both pass.

Signed-off-by: flemming-it <sf@flemming.it>

src/lib.rs

@@ -56,11 +56,8 @@ pub fn invoke(_ctx: Context, inputs: Inputs) -> Result<Outputs, ModuleError> {
     ];
 
     let mean = values.iter().map(|(_, v)| *v).sum::<f32>() / values.len() as f32;
-    let variance = values
+    let variance =
-        .iter()
+        values.iter().map(|(_, v)| (v - mean).powi(2)).sum::<f32>() / values.len() as f32;
-        .map(|(_, v)| (v - mean).powi(2))
-        .sum::<f32>()
-        / values.len() as f32;
     let dispersion = variance.sqrt();
 
     let mut dims = BTreeMap::new();