Emit a warning when customers have unsafe bundles ranges

Some customers have unsafe versions references crossing major versions (e.g., [4.0.0, 5.2.0)), this is risky, as they'd end up getting a new, potentially breaking, major version once that becomes available.

We should emit a diagnostic event/warning when we detect those scenarios, with guidance on how to fix.

Start by locating where customer bundle version ranges are parsed or validated and review existing diagnostic warning patterns. Reproduce or test a range that crosses major versions, then verify that detection emits a warning with guidance for narrowing the range.

Written by the indexing model from the issue text.