fix: move ajv to dependencies and auto-install deps in install scripts

`ajv` is required at runtime by the installer (`scripts/lib/install/config.js`)
but was listed under `devDependencies`. This caused `Error: Cannot find module
'ajv'` when running `./install.sh` from a fresh git clone or via `npx`.

- Move `ajv` from devDependencies to dependencies in package.json
- Add auto `npm install` in install.sh when node_modules is missing
- Add matching auto-install in install.ps1 for Windows parity

install.ps1

@@ -34,5 +34,14 @@ while ($true) {
 $scriptDir = Split-Path -Parent $scriptPath
 $installerScript = Join-Path -Path (Join-Path -Path $scriptDir -ChildPath 'scripts') -ChildPath 'install-apply.js'
 
+# Auto-install Node dependencies when running from a git clone
+$nodeModules = Join-Path -Path $scriptDir -ChildPath 'node_modules'
+if (-not (Test-Path -LiteralPath $nodeModules)) {
+    Write-Host '[ECC] Installing dependencies...'
+    Push-Location $scriptDir
+    try { & npm install --no-audit --no-fund --loglevel=error }
+    finally { Pop-Location }
+}
+
 & node $installerScript @args
 exit $LASTEXITCODE

install.sh

@@ -14,4 +14,10 @@ while [ -L "$SCRIPT_PATH" ]; do
 done
 SCRIPT_DIR="$(cd "$(dirname "$SCRIPT_PATH")" && pwd)"
 
+# Auto-install Node dependencies when running from a git clone
+if [ ! -d "$SCRIPT_DIR/node_modules" ]; then
+    echo "[ECC] Installing dependencies..."
+    (cd "$SCRIPT_DIR" && npm install --no-audit --no-fund --loglevel=error)
+fi
+
 exec node "$SCRIPT_DIR/scripts/install-apply.js" "$@"

package.json

@@ -110,11 +110,11 @@
   },
   "dependencies": {
     "@iarna/toml": "^2.2.5",
+    "ajv": "^8.18.0",
     "sql.js": "^1.14.1"
   },
   "devDependencies": {
     "@eslint/js": "^9.39.2",
-    "ajv": "^8.18.0",
     "c8": "^10.1.2",
     "eslint": "^9.39.2",
     "globals": "^17.1.0",