summarisebig 0.1.0

Initial release

• Arrow-first grouped summaries via summarise_big().
• Explicit Arrow reduction plus R finalization with strategy = "map_reduce".
• Bounded complete-group materialization via parallel_chunks and shared_chunk.
• Optional Mirai/Futurize parallelism and Mori shared memory.
• User functions referenced inside captured summary quosures are identified with future::getGlobalsAndPackages() and supplied explicitly to futurized workers.
• The caller’s Future plan is restored after every exit path.
• Default worker count is 2.
• Added a runnable Getting Started vignette covering all four execution paths.
• Added pkgdown configuration and GitHub setup instructions for the project website and continuous R CMD check.