Correct confidence range validation

[kingthorin]

This issue was pointed out by Grok while checking that issue #9 was completed.

The confidence range check is currently incorrect due to Python operator chaining.

prove_confidence_bug.py

#!/usr/bin/env python3
"""Prove the confidence range check bug in technology_validator.py"""

def buggy_check(tag_value: str) -> bool:
    """Replicates the exact logic from _validate_tags"""
    if not tag_value.isnumeric():
        return False  # rejected as non-numeric
    # The buggy line:
    if 0 >= int(tag_value) >= 100:
        return False  # this never triggers
    return True  # accepted


# Test cases that should be rejected but aren't
test_values = ["-5", "0", "50", "100", "101", "999", "abc"]

print("tag_value | isnumeric | buggy_check result | expected")
print("-" * 55)
for v in test_values:
    is_num = v.isnumeric()
    result = buggy_check(v)
    # Expected: True only for 0 <= x <= 100
    try:
        expected = 0 <= int(v) <= 100 if is_num else False
    except ValueError:
        expected = False
    status = "BUG" if result != expected else "ok"
    print(f"{v:9} | {str(is_num):9} | {str(result):17} | {expected}  ({status})")

print()
print("Demonstration of the chained comparison:")
for x in [-5, 0, 50, 100, 101]:
    print(f"  0 >= {x} >= 100  →  {0 >= x >= 100}")

tag_value	isnumeric	buggy_check result	expected
-5	False	False	False (ok)
0	True	True	True (ok)
50	True	True	True (ok)
100	True	True	True (ok)
101	True	True	False (BUG)
999	True	True	False (BUG)
abc	False	False	False (ok)

Demonstration of the chained comparison:
0 >= -5 >= 100 → False
0 >= 0 >= 100 → False
0 >= 50 >= 100 → False
0 >= 100 >= 100 → False
0 >= 101 >= 100 → False

[kingthorin]

Luckily the existing data/values all seem to be in the appropriate/expected range.

Count	Value
108	50
46	25
16	0
10	75
5	99
5	80
…	…