Enable recording with Replay and add more examples

[markerikson]

This PR:

• Enables recording benchmarks with https://replay.io , so that I can inspect code behavior and do some analysis-based performance profiling
• Updates to a new rev of the 8.1.0-autotracking build
• Tweaks the many-slices example to have some nested counter state
• Copy-pastes the RTKQ example from https://github.com/phryneas/rtkq-performance-testbench

Interestingly, the first run of that RTKQ example looks like this:

Results for benchmark rtkq-separate-queries:
┌────────────────────┬─────────┬──────────────┬─────────────────────────────────────────────────────────────────────┐
│ Version            │ Avg FPS │ Render       │ FPS Values                                                          │
│                    │         │ (Mount, Avg) │                                                                     │
├────────────────────┼─────────┼──────────────┼─────────────────────────────────────────────────────────────────────┤
│ 8.1.0-autotracking │ 55.14   │ 118.0, 1.0   │ 4,49,39,38,43,58,60,59,60,59,60,59,60,59,60,59,60,59,60,59,60,59,59 │
├────────────────────┼─────────┼──────────────┼─────────────────────────────────────────────────────────────────────┤
│ 8.1.1              │ 10.73   │ 108.8, 1.2   │ 14,17,16,15,1,12,14,4,11,12,13,10,2,11,10,9,11,9,4,9,9              │
└────────────────────┴─────────┴──────────────┴─────────────────────────────────────────────────────────────────────┘

Hopefully encouraging for real-world usage?