Strip the collector/aggregator/postproc/snapshot, vastai sampler+shipper,
host/iroh/subprocess/swim introspection, relay observability, sink/spool, and the diag
binaries; drop the t_diag_* tests. Remove DiagEvent emission from iroh_driver. Add
datastream emit/wire (mux + NoopSink/UdpFrameSink/ClusterFrameSink) and rewire the
dashboard onto datastream_source.
Signed-off-by: Zachery Aaron Shores-Chmielewski <zacheryasc@gmail.com>
