adapters: openai is a static-key vendor

One registry line — `"openai": StaticKey`. The generic static-key adapter
already serves any vendor (accept is the vendor-independent seal, deliver is the
value unchanged, and refresh/identity/usage are not implemented), so a second
static-key vendor is data, not code. The shape-selection test now asserts
For("openai") reports static-key.

Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF

internal/licences/adapters/adapters.go

@@ -167,6 +167,7 @@ type UsageRow struct {
 var registry = map[string]Shape{
 	"anthropic":         RefreshableGrant,
 	"anthropic-api-key": StaticKey,
+	"openai":            StaticKey,
 }
 
 // For returns the adapter for a vendor, refusing an unknown one clearly.

internal/licences/adapters/adapters_test.go

@@ -22,6 +22,16 @@ func TestTheTwoShapesAreSelectedByVendor(t *testing.T) {
 	if grant.Shape() != RefreshableGrant {
 		t.Fatalf("anthropic is %q, expected refreshable-grant", grant.Shape())
 	}
+
+	// openai is a second static-key vendor, served by the same generic adapter — the registry line is
+	// the whole of its integration, and it reports the static-key shape like any other.
+	openai, err := For("openai")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if openai.Shape() != StaticKey {
+		t.Fatalf("openai is %q, expected static-key", openai.Shape())
+	}
 }
 
 // The type assertion is what gates the carve-out: a static key is not a Refresher, so it can never