v3.28.3: the outfile ADM byte-pair rule

The review of v3.28.2 found the parser accepting an odd-length ADM (e.g.
12345), while /api/verify-adm requires byte pairs
((?:[0-9A-F]{2}){2,8}) - the stored value could never verify and was
refused with a misleading "adm must be 4-16 hex digits".

The parser now applies the verifier's exact rule: an odd length (a half
byte) or a value over 16 digits is dropped at import time with "ADM is
not 4-16 hex digits in byte pairs".

Docs: help EN/RU, api.md and the repo AGENTS say "4-16 hex digits in
byte pairs".  Tests: the odd-length and the over-16 drop cases (both
real samples are even-length and unaffected: BAP 3632333239463337,
AM0027 CFA3DD9C6B7F0F8C).  915 frontend + 925 Python; sw cache
simple-v441.

tests/test_outfile.py

@@ -262,6 +262,22 @@ class OptionTests(unittest.TestCase):
         self.assertNotIn('adm', res['presets'][0])
         self.assertTrue(any('ADM is not 4-16 hex digits' in s
                             for s in res['report']['skipped']))
+        # an odd length is a half byte: /api/verify-adm would always refuse the
+        # stored value, so it is dropped at import time (v3.28.3)
+        text = ('ICCID KIC1 KID1 ADM\n' + DIGITS_F + ' ' + K16A + ' ' + K16B +
+                ' 12345\n')
+        res = outfile.parse_outfile(text)
+        self.assertNotIn('adm', res['presets'][0])
+        self.assertTrue(any('ADM is not 4-16 hex digits in byte pairs' in s
+                            for s in res['report']['skipped']))
+        # ...and so is a value over the 16-digit limit (the verifier pads to 8
+        # CHV bytes, a longer value would overflow)
+        text = ('ICCID KIC1 KID1 ADM\n' + DIGITS_F + ' ' + K16A + ' ' + K16B +
+                ' ' + 'AB' * 9 + '\n')
+        res = outfile.parse_outfile(text)
+        self.assertNotIn('adm', res['presets'][0])
+        self.assertTrue(any('ADM is not 4-16 hex digits in byte pairs' in s
+                            for s in res['report']['skipped']))
         # a present but invalid PIN is dropped, the card kept
         text = ('ICCID KIC1 KID1 PIN1\n' + DIGITS_F + ' ' + K16A + ' ' + K16B + ' 12\n')
         res = outfile.parse_outfile(text)