chore(rust): add canonical project checker templates

Add the derive, documentation-width, and test-naming checker exemplars
to the shared Rust template and propagate executable byte-identical copies
to every Rust project;

Author: synesissoftware

scripts/check_derives.py

@@ -1,3 +1,4 @@
+#! /usr/bin/env python3
 """
 Verify DERIVE_LAYOUT: multi-trait `#[derive(...)]` macros must be split
 into separate single-trait lines, ordered alphabetically by trait name,

scripts/check_doc_76.py

@@ -1,3 +1,4 @@
+#! /usr/bin/env python3
 """
 Verify DOC_76: public documentation comment lines are at most 76 characters.
 

scripts/check_test_names.py

@@ -1,3 +1,4 @@
+#! /usr/bin/env python3
 """
 Verify RUST_TEST_NAMING: test functions and test modules use TEST_ prefix
 and SHOUTING_SNAKE_CASE, except words that name a specific Rust construct
@@ -43,8 +44,8 @@ def atom_violation(atom: str) -> str | None:
         return None
 
     return (
-        f"segment '{atom}' must be SHOUTING_SNAKE_CASE, a PascalCase construct name, "
-        "or a Rust snake_case identifier"
+        f"segment '{atom}' must be SHOUTING_SNAKE_CASE, a PascalCase construct "
+        "name, or a Rust snake_case identifier"
     )
 
 
@@ -58,7 +59,7 @@ def parse_padded_construct(
     while i < len(segments) and not segments[i]:
         i += 1
     if i >= len(segments):
-        return None, i, [f"empty segment padding without construct"]
+        return None, i, ["empty segment padding without construct"]
 
     seg = segments[i]
     atom: str | None = None
@@ -82,7 +83,7 @@ def parse_padded_construct(
             violations.append(reason)
         i += 1
     else:
-        return None, start, [f"empty segment padding without construct"]
+        return None, start, ["empty segment padding without construct"]
 
     while i < len(segments) and not segments[i]:
         i += 1
@@ -144,8 +145,8 @@ def parse_name_atoms(rest: str) -> tuple[list[str], list[str]]:
             continue
 
         violations.append(
-            f"segment '{seg}' must be SHOUTING_SNAKE_CASE, a PascalCase construct name, "
-            "or a Rust snake_case identifier"
+            f"segment '{seg}' must be SHOUTING_SNAKE_CASE, a PascalCase construct "
+            "name, or a Rust snake_case identifier"
         )
         i += 1