detect/engine-analyzer: add rule analyzer warnings about rules that could use the frame keyword/semantics/feature
With the addition of frame support, the rule analyzer could now also check for rules with patterns like:
- For SMB traffic: check for content "|FF|" or "|FE|" (especially with "startswith")
- For TLS traffic: check for contents "|16 03 03|" (especially with "startswith")
- ... similar patterns for other protocols
And issue warnings that those can be converted to the new frame semantics.
This task must wait on the definition of the frame keyword/semantics syntax.