internal/pipewire: implement Core::Info and generation footer

These are not directly related but are first encountered on the same message in the capture.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/pipewire/header_test.go

@@ -35,6 +35,12 @@ func TestHeader(t *testing.T) {
 			Size:   0x28, Sequence: 3, FileCount: 0,
 		}, nil},
 
+		{"PW_CORE_EVENT_INFO", []byte(recvmsg00Message00Header), pipewire.Header{
+			ID:     pipewire.PW_ID_CORE,
+			Opcode: pipewire.PW_CORE_EVENT_INFO,
+			Size:   0x6b8, Sequence: 0, FileCount: 0,
+		}, nil},
+
 		{"PW_SECURITY_CONTEXT_METHOD_CREATE", []byte{
 			// Id
 			3, 0, 0, 0,