Import Melee matches exports, add tests and local podman stack

- Parse Melee matches exports (one round per file, byes, null GameWins);
  one import form detects matches vs standings exports. Re-importing a
  round replaces just that round and keeps entered decks.
- Per-player deck entry for sessions scored from matches.
- node:test suite with anonymised fixtures; lockfile.
- scripts/local.sh runs the compose stack under podman with its own
  .env.local, project name and volume.
- README and CLAUDE.md docs.

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

scripts/local.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+# Run the docker compose stack locally with podman, isolated from the real .env and data.
+# usage: scripts/local.sh up | down | reset | logs | ps
+# First run writes .env.local (random secrets, bound to 127.0.0.1). Set BASE_PATH or COOKIE_SECURE there to test them.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+
+if [[ ! -f .env.local ]]; then
+  cat > .env.local <<EOF
+DB_PASSWORD=$(openssl rand -hex 16)
+SECRET_KEY=$(openssl rand -hex 32)
+ADMIN_PASSWORD=local-$(openssl rand -hex 6)
+COOKIE_SECURE=false
+BIND_ADDR=127.0.0.1
+HOST_PORT=8889
+BASE_PATH=
+EOF
+  echo "wrote .env.local"
+fi
+
+compose() { podman compose --env-file .env.local -p mtg-local "$@"; }
+case "${1:-up}" in
+  up)
+    compose up -d --build --wait
+    set -a; source .env.local; set +a
+    echo "http://127.0.0.1:${HOST_PORT}${BASE_PATH}/  admin password: ${ADMIN_PASSWORD}"
+    ;;
+  down) compose down ;;
+  reset) compose down -v ;; # also deletes the local database volume
+  logs) compose logs -f ;;
+  ps) compose ps ;;
+  *) echo "usage: $0 up|down|reset|logs|ps" >&2; exit 1 ;;
+esac