Add examples catalog with subcommand dispatch

- Extract game engine from package main to engine/ library package
- Create examples/ package with registry, Entry type, and BuilderDeps
- Register default world as an example (moved from main())
- Add combat example: two teams of units facing each other
- Rewrite main.go as thin dispatch: go run . example [name]
- Update README with examples catalog one-liner

1 files changed, 0 insertions, 53 deletions

diff --git a/spawn.go b/spawn.go
deleted file mode 100644
index 87624fb..0000000
--- a/spawn.go
+++ /dev/null
@@ -1,53 +0,0 @@
-package main
-
-import (
-	"log/slog"
-	"time"
-
-	"age_of_empires/ecs"
-	"age_of_empires/monad"
-	"age_of_empires/physics"
-)
-
-type SpawnRequest struct {
-	Start time.Time
-}
-
-type Spawn struct {
-	UnitResourceCost  int
-	UnitSpawnDuration time.Duration
-	Requests          []SpawnRequest
-	SpawnTarget       monad.Option[physics.Point]
-}
-
-func NewSpawn(unitResourceCost int, unitSpawnDuration time.Duration) Spawn {
-	return Spawn{
-		UnitResourceCost:  unitResourceCost,
-		UnitSpawnDuration: unitSpawnDuration,
-		Requests:          make([]SpawnRequest, 0),
-	}
-}
-
-func UpdateSpawnSystem(g *Game, now time.Time, masks []ecs.Mask, spawns []Spawn, positions []physics.Point) {
-	required := ecs.CM_Position | ecs.CM_Spawn
-	for i, mask := range masks {
-		if mask&required == required {
-			spawn := &spawns[i]
-			position := positions[i]
-			if len(spawn.Requests) == 0 || now.Sub(spawn.Requests[0].Start) < time.Duration(spawn.UnitSpawnDuration) {
-				continue
-			}
-			spawnPosition, _ := physics.Closest(position, physics.AdjacentPoints(position), g.getMoveMap())
-			unit := g.Append(g.UnitBuilder.WithPosition(spawnPosition).Build())
-			slog.Info("Spawned unit")
-			if spawn.SpawnTarget.Ok {
-				slog.Info("Unit has spawn target")
-				MainAction(g, unit, spawn.SpawnTarget.Value, g.getMoveMap())
-			}
-			spawn.Requests = spawn.Requests[1:]
-			if len(spawn.Requests) > 0 {
-				spawn.Requests[0].Start = now
-			}
-		}
-	}
-}