LOS ANGELES—William Shatner’s durable role as an avatar of space’s promise drew a frenzy of attention when fiction became fact with his rocket ride. The “Star Trek” actor says he was as surprised by it as he was gratified by the 10-minute, suborbital jaunt made possible by billionaire Jeff Bezos. The experience is the subject of “Shatner in Space,” a hour-long special out Wednesday on Amazon Prime Video. It details last October’s flight that made Shatner, 90, the oldest person to reach space. Bezos credits “Star Trek” with igniting his interest in space travel. Shatner, whose decades-long career includes “The Defenders,” “T.J. Hooker,” and “Boston Legal” along with the original “Star Trek” series and films, wanted to be part of Bezos’ Blue Origin launch last July, its first with passengers. Shatner saw joining trip No. 2 akin to being named vice president when the Oval Office was the dream. He …