RemapBundle

The mojmap<->runtime remap bundle in force: a mappings file, and the symbol dir holding MC_SYMBOLS (plus DEPS_LIST where one was harvested). Private constructor — mappings without symbols leaves scripts compiling against the runtime jar, where no mojmap name resolves, so neither factory below can produce that pair.

The dir's layout lives here rather than in its readers because ClasspathCollector drops the runtime MC jar on the mere EXISTENCE of a bundle: what makes a dir a bundle has to have exactly one answer.

Must stay in ...repl, NOT repl.impl: MaskingClassLoader delegates this package to the parent, which is what lets the masking-loaded ScriptWeave / RemapCacheBuilder and the game-loaded ReplBridge read one copy.