add reporting for virg and inityr for predators

[Rick-Methot-NOAA]

What issue(s) does this PR address? Describe and add issue numbers, if applicable.

Link issue(s) here:
none

What tests have been done? Upload any model input files created for testing in a zip file, if possible.

visual exam using vendance model

What tests/review still need to be done? Who can do it, and by when is it needed (ideally)?

the gha will be sufficient

Check which is true. This PR requires:

• [ x] no further changes to r4ss
• [ x] no further changes to the manual
• [x ] no further changes to SSI (the SS3 GUI)
• [x ] no further changes to the stock synthesis change log (new features, bug reports)

Describe any changes in r4ss/SS3 manual/SSI/change log that are needed (if not checked):

none

Additional information (optional):

This change fills in blanks for pred_M2 and associated catch for the virgin and initial equilibrium years

[Rick-Methot-NOAA]

While working on this issue, I discovered that the predator approach in 3.30.18.00 was flawed and did not handle time-varying pred_M2 correctly. This problem with 3.30.18 was fixed by #307 and #310, with the final clean-up happening here.