Nightly builds and integration testing pt 3

Improvements to folio-snapshot and folio-snapshot-stable CI pipelines for more stability and reliability. The focus is on UI (single modules and platforms) builds and tests as this is where we are seeing most issues.

This includes:

• consistency across dev and CI builds
• better build reproducibility and dependency management (locking)
• consistent build and test invocation and results (stripes-cli)
• hierarchical structure of platforms (platform-complete < platform-core)