Lowercase and CamelCase checking of module imports in UMDP3 checker

@Pierre-siddall đang làm issue này rồi.

Từ ngày 28/4/2026.

During the runtime of `umdp3_conformance.py` it was noted that changing module imports to be uppercase did not result in a failure being registered in the output of the script as expected. `umdp3_conformance.py` calls the following code in `umdp3_checker_rules.py`

```python
def lowercase_variable_names(self, lines: List[str]) -> TestResult:
"""Check for lowercase or CamelCase variable names only"""
"""
TODO: This is a very simplistic check and will not detect many
cases which break UMDP3. I suspect the Perl Predecessor concatenated
continuation lines prior to 'cleaning' and checking. Having identified
a declaration, it also then scanned the rest of the file for that
variable name in any case."""
failures = 0
error_log = {}
count = -1
for count, line in enumerate(lines):
clean_line = self.remove_quoted(line)
clean_line = re.sub(r"!.*$", "", clean_line)

# Simple check for UPPERCASE variable declarations
if re.search(
r"^\s*(INTEGER|REAL|LOGICAL|CHARACTER|TYPE)\s*.*::\s*[A-Z_]+",
clean_line,
re.IGNORECASE,
):
clean_line = re.sub(
r"^\s*(INTEGER|REAL|LOGICAL|CHARACTER|TYPE)\s*.*::\s*",
"",
clean_line,
)
if match := re.search(r"([A-Z]{2,})", clean_line):
self.add_extra_error(f"UPPERCASE variable name : {match[1]}")
failures += 1
error_log = self.add_error_log(
error_log, f"UPPERCASE variable name {match[1]}", count +1
)

output = f"Checked {count + 1} lines, found {failures} failures."
return TestResult(
checker_name="Lowercase or CamelCase variable names only",
failure_count=failures,
passed=(failures == 0),
output=output,
errors=error_log,
)
```

addressing this issue will involve a refactor of this function to ensure module level imports are checked.