fix(lf): per-protocol identify label (native HID/AWID/FDX-B no longer KeyError)

identify_lf built its label from emitted['id_hex'], which only EM4100 provides — a
native HID/AWID/FDX-B tag (no T5577 config) would KeyError. Add credential_label() to
format each decoder's own fields: "HID Prox H10301 FC.. Card..", "AWID-26 FC.. Card..",
"FDX-B 124-000000000555 (animal)", "EM4100 <id>". Tests for native FDX-B + HID labels.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

pm3py/lf/capture.py

@@ -22,6 +22,20 @@ _DECODERS = (
 )
 
 
+def credential_label(c: dict) -> str:
+    """One-line name for a decoded credential, per protocol (each decoder returns its own fields)."""
+    p = c.get("protocol", "?")
+    if p == "EM4100":
+        return f"EM4100 {c['id_hex']}"
+    if p == "HID Prox":
+        return f"HID Prox {c['format']} FC {c['facility_code']} Card {c['card_number']}"
+    if p == "AWID":
+        return f"{c['format']} FC {c['facility_code']} Card {c['card_number']}"
+    if p == "FDX-B":
+        return f"FDX-B {c['id']}" + ("  (animal)" if c.get("animal") else "")
+    return p
+
+
 def demod_samples(samples) -> dict | None:
     """Decode a raw LF envelope to a credential by trying each protocol demod in turn.
 
@@ -87,13 +101,13 @@ def identify_lf(device, emit=None) -> dict | None:
              f"({config['modulation']}, RF/{config['data_bit_rate']}, {config['max_block']} blocks)"
              f"  -> {emulating}")
     if emitted is not None:
-        emit(f"  emitted: {emitted['protocol']} id {emitted['id_hex']}")
+        emit(f"  emitted: {credential_label(emitted)}")
 
     # label: prefer the physical chip + what it emulates; else the emitted credential
     if chip:
         label = f"{chip} ({emulating})"
     else:
-        label = f"{emitted['protocol']} {emitted['id_hex']}"
+        label = credential_label(emitted)
 
     return {
         "found": True,

tests/test_lf_demod.py

@@ -343,6 +343,19 @@ class TestIdentifyLF:
         assert r["found"] and r["chip"] is None
         assert r["label"] == "EM4100 1122334455"
 
+    def test_native_fdxb_label(self):
+        # a native FDX-B tag (no T55xx) must label per-protocol, not KeyError on id_hex
+        dev = _mock_lf_device(config_env=bytes([128] * 4000),
+                              emitted_env=_fdxb_env(124, 555, animal=1))
+        r = identify_lf(dev)
+        assert r["found"] and r["chip"] is None
+        assert r["label"].startswith("FDX-B 124-000000000555")
+
+    def test_native_hid_label(self):
+        dev = _mock_lf_device(config_env=bytes([128] * 4000), emitted_env=_hid_env(12, 3456))
+        r = identify_lf(dev)
+        assert r["label"] == "HID Prox H10301 FC 12 Card 3456"
+
     def test_nothing_on_antenna(self):
         dev = _mock_lf_device(config_env=bytes([128] * 4000), emitted_env=bytes([128] * 4000))
         assert identify_lf(dev) is None