Two fixes after the M31-M37 round.

**Clients froze on a busy machine**

Test bots, and on a busy PC any client, could freeze for seconds and then be dropped by the server. The cause was reading effect entries from the game's effects archive on the main thread: the archive is one compressed stream, so each read unpacks everything before the entry, and under CPU load one frame could take 5 s or more. Effects, decal textures and the shell casing are now loaded in the background, the effects player only does lookups, and startup loads effects in one pass (about 9 s before, one pass now). A frame watchdog for test bots reports slow frames by phase, and a bot that loses its connection says why. Before the fix two bots froze within 2-40 s under load; after it, a 200 s run under heavier load stayed connected throughout.

**One sprint animation for every class**

Following the owner's knowledge of the original, all classes now play the same multiplayer sprint loop (the strafe left, forward and strafe right clips of the multiplayer sprint). The per-weapon sprint clips for the heavy bolter and lascannon/plasma cannon are still read but no longer used; `--per-weapon-sprint` shows them for comparison.

**Status**

The freeze fix was reviewed independently and measured under load. The sprint change is small and client-only and has not been seen in play by a person yet.

*Unofficial fan project: not affiliated with or endorsed by Games Workshop, Relic, THQ, Sega or Focus. Screenshots show original game assets rendered from the owner's own install of Warhammer 40,000: Space Marine (2011); no game files are distributed.*