feat: plugin to apply optical photon efficiency on generation

[wdconinc]

Briefly, what does this PR introduce?

This adds a stacking action plugion to apply final quantum efficiency for optical photons as an effective generation efficiency by suppressing at stacking.

TODO:

• [x] Needs testing: tested and works.

What kind of change does this PR introduce?

• [ ] Bug fix (issue #__)
• [x] New feature (issue #__)
• [ ] Documentation update
• [ ] Other: __

Please check if this PR fulfills the following:

• [ ] Tests for the changes have been added
• [ ] Documentation has been added / updated
• [ ] Changes have been communicated to collaborators

Does this PR introduce breaking changes? What changes might users need to make to their code?

No.

Does this PR change default behavior?

No. Optical photons are not enabled by default in the DIRC since none of the materials support optical photons.

[wdconinc]

@veprbl This is not required for 24.03.0.

[veprbl]

Do optical processes trigger stacking action? Because, if they do, the efficiency will be applied multiple times. Is it possible add a debug printout to display creator process, possibly assert that it has to be scintillation/cherenkov?

[wdconinc]

Stacking action applies to new particles. The only optical process that should add secondaries is WLS (and WLS2). Optical boundary processes change the same particle so it undergoes reflection, transmission, or absorption.

Tests comparing the received optical photon energy spectrum at the hpDIRC sensor plane indicate that this plugin applies the efficiency only once. I can post some plots later.

[wdconinc]

Comparison without (top) and with efficiency (bottom) (for different random seeds).

[wdconinc]

There are a substantial number of calls to classifyNewTrack(), but they are all no-ops. I added some more diagnostic output in VERBOSE, and a counter in DEBUG that indicates what fraction of photons was killed. I'll file a new PR for that.