[tintinhamans]

FrameRateLimit::wait restarts its period when it wakes up, so a frame that runs over the period loses that time for good. In network games the logic runs at most one frame per render pass, so at the 60 cap the logic slows down with it, and Network::timeForNewFrame throws the time away once it is a frame behind.

The next deadline is now the previous one plus a period. Lateness is made up on the next frames, pauses longer than a period are dropped instead of banked.

Two clients at a 60 cap with logic at 60, 3 runs each:

• steady ~15 ms frames: 59.86 → 59.96 logic fps, schedule resets 11.8 → 1.5 per 10 s
• uneven frames (8/22 ms, some over the period): 49.2 → 58.4 logic fps

CRC matched in all runs. FrameRateLimit is the same upstream, so this goes there too.