feat: implement AI gateway phase one runtime

scripts/dev.sh

@@ -1,6 +1,50 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+PROJECT_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+stop_stale_api_processes() {
+  local api_port="${HTTP_ADDR:-:8088}"
+  api_port="${api_port##*:}"
+  local api_cwd="${PROJECT_ROOT}/apps/api"
+
+  if command -v pgrep >/dev/null 2>&1; then
+    while read -r pid; do
+      [[ -z "$pid" || "$pid" == "$$" ]] && continue
+      local cwd
+      cwd="$(lsof -a -p "$pid" -d cwd -Fn 2>/dev/null | awk '/^n/ {print substr($0, 2); exit}')"
+      if [[ "$cwd" == "$api_cwd" ]]; then
+        echo "[ai-gateway] stopping stale go-watch process: ${pid}"
+        kill "$pid" 2>/dev/null || true
+      fi
+    done < <(pgrep -f "go-watch\\.mjs -- go run ./cmd/gateway" || true)
+  fi
+
+  if ! command -v lsof >/dev/null 2>&1; then
+    return
+  fi
+
+  local pids
+  pids="$(lsof -tiTCP:"$api_port" -sTCP:LISTEN 2>/dev/null || true)"
+  [[ -z "$pids" ]] && return
+
+  while read -r pid; do
+    [[ -z "$pid" ]] && continue
+    local cwd command
+    cwd="$(lsof -a -p "$pid" -d cwd -Fn 2>/dev/null | awk '/^n/ {print substr($0, 2); exit}')"
+    command="$(ps -p "$pid" -o command= 2>/dev/null || true)"
+    if [[ "$cwd" == "$api_cwd" || "$command" == *"easyai-ai-gateway"* ]]; then
+      echo "[ai-gateway] freeing API port ${api_port}, stopping stale process: ${pid}"
+      kill "$pid" 2>/dev/null || true
+    else
+      echo "[ai-gateway] port ${api_port} is used by an unrelated process: ${pid} ${command}" >&2
+      exit 1
+    fi
+  done <<< "$pids"
+
+  sleep 0.5
+}
+
 if [[ -z "${AI_GATEWAY_PG_CONTAINER:-}" ]]; then
   if docker inspect easyai-pgvector >/dev/null 2>&1; then
     export AI_GATEWAY_PG_CONTAINER="easyai-pgvector"
@@ -26,4 +70,5 @@ echo "[ai-gateway] using database: ${AI_GATEWAY_DATABASE_URL}"
 
 scripts/create-database.sh
 pnpm nx run api:migrate
+stop_stale_api_processes
 exec pnpm nx run-many -t dev -p api web --parallel=2