Tomatoes, match tabs, shared pings, and a round of fixes

- On the results, everyone but the winner splats tomatoes where they
  click (bots aim at the winner), with a new splat sound.
- During a match the menu has the item tabs (choosing when the
  countdown allows, and otherwise levelling the sandbox's levels for
  when you're back), Play (the game's rules) and Settings.
- Pings are shared through the server (protocol 4), so other players'
  connection bars show over their heads and on their windows.
- PvP comes into lobbies with your profile and is saved.
- The choice menu opens by itself however the countdown began.
- Knocked-out fighters keep their buttons current, so Ready on the
  results toggles once per press.
- The weapon wheel wraps both ways. Readying with empty slots plays
  the equip sound for your own fighter.
- Shock Absorber: up to 50% less weapon movement and 33% less
  knockback. Only the catalog previews the next level.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/effects.h

@@ -58,6 +58,18 @@ struct Ring
     float radius = 0;
 };
 
+constexpr int SPLAT_BLOBS = 6;
+
+// A tomato's splat: blobs of colour round where it landed, fading out.
+struct Splat
+{
+    Color color;
+    Vec2 position;
+    Vec2 blobs[SPLAT_BLOBS];
+    float sizes[SPLAT_BLOBS];
+    float life = 0;
+};
+
 // A fading copy of a sprite left behind by something moving fast.
 struct Afterimage
 {
@@ -73,6 +85,7 @@ public:
     void afterimage_spawn(Pose pose);
     void flash_spawn(Vec2 position, float angle, float size, Color color);
     void ring_spawn(Vec2 position, float radius, Color color);
+    void splat_spawn(Vec2 position, Color color);
     void afterimage_draw(Game& game);
     void number_spawn(Vec2 position, int value, int target, Color color);
     void dps_record(int amount);
@@ -91,6 +104,7 @@ private:
     std::vector<Particle> particles;
     std::vector<Popup> popups;
     std::vector<Ring> rings;
+    std::vector<Splat> splats;
     float shake = 0;
     int ticks = 0;
 };