feat: add report generation from JSON

Signed-off-by: James McCorrie <james.mccorrie@lowrisc.org>

Author: machshev

src/dvsim/cli/main.py

@@ -4,18 +4,45 @@
 
 """DVSim CLI main entry point."""
 
+from pathlib import Path
+
 import click
 
+from dvsim.report.data import ResultsSummary
+
 
 @click.group(invoke_without_command=True)
 @click.pass_context
 def main(ctx) -> None:
     """Entry point for DVSim."""
     if ctx.invoked_subcommand is None:
-        from dvsim.cli.run import run  # noqa: PLC0415
+        from dvsim.cli.run import run
 
         run()
 
 
+@main.group()
+def report() -> None:
+    """Reporting helper commands."""
+
+
+@report.command()
+@click.argument(
+    "json_path",
+    type=click.Path(exists=True, file_okay=True, dir_okay=False, path_type=Path),
+)
+@click.argument(
+    "output_dir",
+    type=click.Path(file_okay=False, dir_okay=True, path_type=Path),
+)
+def gen(json_path: Path, output_dir: Path) -> None:
+    """Generate a report from a existing results JSON."""
+    from dvsim.report.generate import gen_summary_report
+
+    results = ResultsSummary.load(path=json_path)
+
+    gen_summary_report(summary=results, path=output_dir)
+
+
 if __name__ == "__main__":
     main()