Remove Apex Dynamics faction, retune bullet speed/size

Drop Apex Dynamics from the playable roster (2 races now: Inner Sphere
Navy, Outer Rim Collective) to simplify the 2D art pipeline; World's
race-offer logic just shuffles both remaining races instead of picking
2 of N. Also fix bullets using a constant muzzle velocity instead of
adding the shooter's own velocity, and shrink the bullet hitbox/sprite.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

overview/overview.md

@@ -2,13 +2,13 @@
 
 ## Concept
 
-A 2D pixel-art top-down space shooter inspired by **Subspace Continuum**, built for **Steam Deck and PC**. Three alien races fight for control of a galaxy. Fast matchmaking like Rocket League — quick in, quick out.
+A 2D pixel-art top-down space shooter inspired by **Subspace Continuum**, built for **Steam Deck and PC**. Two alien races fight for control of a galaxy. Fast matchmaking like Rocket League — quick in, quick out.
 
 ## Core Loop
 
 1. Launch → Main Menu
 2. Enter callsign → click CASUAL
-3. World loads → pick your race (2 of 3 randomly offered per match) → pick your ship
+3. World loads → pick your race (both offered every match) → pick your ship
 4. Fight in a 25v25 battle
 5. Return to main menu
 
@@ -25,7 +25,7 @@ A 2D pixel-art top-down space shooter inspired by **Subspace Continuum**, built
 Main Menu
   └─ CASUAL ──► World loads immediately (game active)
                   └─ TeamSelect overlay appears
-                       ├─ Pick race  (2 random of 3 offered)
+                       ├─ Pick race  (both offered every match)
                        └─ Pick ship  (4 available, sprites shown)
                             └─ Player spawns centred, invincible briefly
                                  └─ ESC / Start ──► Pause menu overlay
@@ -38,7 +38,7 @@ Main Menu
 
 ## Races
 
-3 playable races chosen from a pool of 10 concepts — see `racesclasses.md`. Each race has 5 ship classes:
+2 playable races (a third, Apex Dynamics, was cut to simplify the art pipeline) — see `racesclasses.md`. Each race has 5 ship classes:
 
 | Class | Role |
 |-------|------|
@@ -52,8 +52,8 @@ Races are visually distinct — critical for reading a 25v25 battlefield at a gl
 
 ## Match Setup
 
-- Each match randomly picks **2 of the 3 races** to field
-- Player picks which of those 2 they fight for, then picks their ship
+- Both races are fielded every match (order they're presented in is randomized)
+- Player picks which of the 2 they fight for, then picks their ship
 - Bot fill ensures a minimum of **7v7** in casual; no bots added beyond that
 
 ## Design Philosophy