feat(awards): match on CNTY as it stands, not only keyed to a US state

The award field list offered us_county, which returns STATE,County --
correct for the United States, where Jefferson County exists in several
states, and wrong for every award whose district is already unique. An
RDA reference (RO-19) never matched, and there was no other field to
point an award at.

Adds county, the raw CNTY value, alongside it.

internal/award/fieldvalue_county_test.go

@@ -0,0 +1,29 @@
+package award
+
+import (
+	"testing"
+
+	"hamlog/internal/qso"
+)
+
+// A district lives in CNTY as-is; the US award field keys it to the state
+// because county names repeat across states. Confusing the two silently breaks
+// whichever award is not American.
+func TestCountyFieldIsRawWhileUSCountyIsKeyed(t *testing.T) {
+	q := &qso.QSO{State: "TX", County: "RO-19"}
+	if got := fieldRaw("county", q); got != "RO-19" {
+		t.Fatalf("county = %q, want RO-19", got)
+	}
+	if got := fieldRaw("us_county", q); got == "RO-19" {
+		t.Fatalf("us_county should key the county to its state, got %q", got)
+	}
+	var found bool
+	for _, f := range Fields() {
+		if f == "county" {
+			found = true
+		}
+	}
+	if !found {
+		t.Fatal("county missing from the award field list")
+	}
+}