[stress] watcher doesn't appear to start scheduled crons

Our chaos policies are all based on cron-jobs. We fixed a couple of issues that were preventing them from launching (manually) but it appears there's an issue with the watcher then unpausing the chaos-mesh schedules, which should happen if `chaos: "true"`.

It could be that the chaos value should be a bool, not a string and we can define that more now that more people are generating chaos policies.

Start by tracing the watcher behavior that handles chaos policies and scheduled cron-jobs, then inspect how the `chaos` value is interpreted when it is the string `"true"`. Confirm the expected behavior against chaos-mesh schedules; done means the watcher reliably unpauses schedules for eligible policies and the stress case is covered.

Written by the indexing model from the issue text.