1. Sort cranberries (thaw if frozen) and discard any that are soft or spoiled. Rinse and drain berries, then spread out on towels. Pat gently with more towels to dry quickly.
2. In a 5- to 6-quart pan over high heat, combine orange juice and jelly. Stir, mashing jelly until it melts, about 3 minutes.
3. Add sugar. Stir until syrup begins to smell slightly caramelized and drips slowly from a spoon, about 7 minutes. Immediately remove pan from heat. Add the cranberries and stir to coat with syrup.
4. Return pan to low heat and stir gently until cranberries are evenly warm and no longer taste raw, 3 to 4 minutes (a few berries may pop). Remove from heat and let stand until syrup is cool enough to coat berries evenly, about 20 minutes, stirring occasionally. Then scrape berry mixture into the baked crust, mounding fruit.
5. Seal chocolate in a small zip-lock plastic freezer bag (without pleats). Heat in a microwave oven at 50% power just until chocolate softens, about 2 minutes. Knead chocolate until smooth.
6. With a thin skewer, puncture a hole in 1 corner of the bag. Squeeze chocolate over tart in fine zigzag lines. Chill until chocolate and jelly glaze are firm, at least 30 minutes or up to 1 day. If making ahead, cover when jelly is set. To serve, remove cover and pan rim. Cut tart into wedges.