feat(server): initial implementation

This commit captures the full server code accumulated across
several development sessions. It includes the following layers,
applied in roughly this order during development:

1. Base infrastructure
   - cmd/poc-server HTTP+WebSocket server, /health, /stats
   - internal/transport wire types (Envelope + all message types)
   - internal/catalog, internal/realtime, internal/stats
   - internal/storage/postgres with migrations 001-004
   - .env, .env.example, docker-compose, Dockerfile, scripts/

2. Swagger documentation
   - go get github.com/swaggo/http-swagger
   - swag init produces docs/docs.go
   - /swagger/index.html UI, /swagger/doc.json spec
   - annotations on health/stats/ws and catalog handlers

3. Races API
   - internal/races/{store,service,keyset,types}.go
   - migration 005_races.sql: finished_races, race_plans, race_queue
   - GET /api/races with keyset pagination, status filter
   - GET /api/races/upcoming
   - POST /api/races/queue/join, GET, DELETE
   - POST/GET /api/races/plans, DELETE /{id}
   - lobby.RaceMeta simplification (no host_id/host_name)

4. Races seeder
   - internal/races/seed with deterministic generator
   - --seed-races / --reset CLI flags in main.go
   - 30 finished + 5 live + 5 plans + 4 queue entries

5. Drivers and clans
   - internal/drivers, internal/clans (CRUD, validation)
   - migration 008_drivers_clans.sql
   - /api/clans and /api/drivers endpoints
   - 3-letter uppercase nickname/tag validation
   - lobby.DriverMeta: Nickname, AvatarURL, ClanID, ClanTag

6. Podium
   - internal/transport.RacePodiumEntry
   - lobby.SetDriverProfile for in-memory metadata sync
   - migration 007_podium.sql (podium JSONB column)
   - seeder populates top-3 per finished race

7. Live races persistence
   - migration 009_live_persistence.sql: live_races,
     live_race_drivers, lobby_drivers
   - internal/races/live_store.go: LiveStore with write-side
     mirror for lobby.Service mutations
   - Service.collectLive and Upcoming read from Postgres
   - main.go RestoreFromDB rehydrates lobby on startup

8. Unify live + finished into one races table
   - migration 010_unify_races.sql: rename finished_races to
     races, expand status CHECK, merge live rows
   - PgStore now hosts both write paths; LiveStore is a
     thin facade implementing lobby.Persistence
   - seeder resetAll drops only finished/cancelled rows and
     race_plans / race_queue / lobby_drivers

Each layer is consistent on its own; cross-layer changes are
visible in the file history. A future refactor may split this
commit into the per-stage boundaries listed above.

server/internal/catalog/seeddefs/seeddefs_test.go

@@ -0,0 +1,40 @@
+package seeddefs
+
+import "testing"
+
+func TestTracksFitInRoom(t *testing.T) {
+	const (
+		roomLen = 4.5
+		roomWid = 3.2
+	)
+	for _, tr := range DefaultTracks() {
+		if tr.Bounds.LengthM > roomLen {
+			t.Errorf("track %s: length %.3f m exceeds 4.5 m", tr.ID, tr.Bounds.LengthM)
+		}
+		if tr.Bounds.WidthM > roomWid {
+			t.Errorf("track %s: width %.3f m exceeds 3.2 m", tr.ID, tr.Bounds.WidthM)
+		}
+		if len(tr.Centerline) < 8 {
+			t.Errorf("track %s: too few waypoints (%d)", tr.ID, len(tr.Centerline))
+		}
+		t.Logf("%-30s %5.2fm x %5.2fm  %2d waypoints", tr.ID,
+			tr.Bounds.LengthM, tr.Bounds.WidthM, len(tr.Centerline))
+	}
+}
+
+func TestCarsValid(t *testing.T) {
+	for _, c := range DefaultCars() {
+		if c.LengthMm < 200 || c.LengthMm > 260 {
+			t.Errorf("car %s: length %.0f mm out of F1 1/24 range (200..260)", c.ID, c.LengthMm)
+		}
+		if c.WidthMm < 70 || c.WidthMm > 100 {
+			t.Errorf("car %s: width %.0f mm out of F1 1/24 range", c.ID, c.WidthMm)
+		}
+		if c.Motor.PowerW < 500000 {
+			t.Errorf("car %s: power %.0f W too low for F1 PU", c.ID, c.Motor.PowerW)
+		}
+		t.Logf("%-35s %dx%dx%d mm, %d W, %d m/s", c.ID,
+			int(c.LengthMm), int(c.WidthMm), int(c.HeightMm),
+			int(c.Motor.PowerW), int(c.TopSpeedMs))
+	}
+}