There could be an arbitrary glottal stop in the place of the hyphen. The glottal stop is obligatory for double "l". Thus the pronunciation of "byli" and "byl-li" is clearly different. The l's in the latter are clearly separated in different syllables. No, there is no schwa. Nucleus of Czech syllables consists of one single phone, either of vowel (a, á, e, é, i, í, o, ó, u, ú), or of a diphthong (ou, au, eu), or of a syllabic consonant (r, l, m, s) which is always preceded by onset.