Replaces the placeholder stub that returned EXIT_PENDING with a real
analyze --config <yaml> [--output <json>] command. Loads the YAML,
validates through AnalysisConfig (so typos fail with a clear
ValidationError before any predictions load), runs the pipeline,
and writes the AnalysisReport atomically.
Surfaces YAML parse errors and schema violations as EXIT_USAGE=2
with messages pointing at the offending file. Missing predictions
files during execution also surface as EXIT_USAGE rather than a
bare traceback.
Prints a one-line summary after the run: segmentation counts, the
analysis kind, and — for DTW — the per-segment distance count and
mean. --output / -o overrides the report path declared in the
config, useful when sweeping a single config over multiple input
pairs from a shell loop.