Add portable structured log viewer bundles

[concordia-claw]

Summary

• add concordia-log bundle to create a portable HTML viewer with a structured log preloaded
• reuse and package the existing log_viewer.html rather than maintaining a second viewer
• safely escape embedded script end tags and Unicode line separators
• document portable viewer creation and the privacy implications of sharing full logs

Testing

• concordia/.venv/bin/python concordia/concordia/command_line_interface/concordia_log_test.py (32 tests)
• bundled a real 188 KB structured simulation log and verified the generated HTML
• built the wheel and verified it contains concordia/utils/log_viewer.html and concordia/utils/log_viewer.py

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.