⬆️ Bump google.golang.org/adk from 1.3.0 to 1.4.0

Bumps [google.golang.org/adk](https://github.com/google/adk-go) from 1.3.0 to 1.4.0.
- [Release notes](https://github.com/google/adk-go/releases)
- [Commits](https://github.com/google/adk-go/compare/v1.3.0...v1.4.0)

---
updated-dependencies:
- dependency-name: google.golang.org/adk
  dependency-version: 1.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

go.mod

@@ -72,7 +72,7 @@ require (
 	github.com/spf13/pflag v1.0.10
 	golang.org/x/sys v0.45.0 // indirect
 	golang.org/x/text v0.37.0 // indirect
-	google.golang.org/adk v1.3.0
+	google.golang.org/adk v1.4.0
 	google.golang.org/api v0.281.0
 	google.golang.org/genai v1.58.0
 	google.golang.org/protobuf v1.36.11 // indirect

go.sum

@@ -147,8 +147,8 @@ golang.org/x/tools v0.44.0 h1:UP4ajHPIcuMjT1GqzDWRlalUEoY+uzoZKnhOjbIPD2c=
 golang.org/x/tools v0.44.0/go.mod h1:KA0AfVErSdxRZIsOVipbv3rQhVXTnlU6UhKxHd1seDI=
 gonum.org/v1/gonum v0.17.0 h1:VbpOemQlsSMrYmn7T2OUvQ4dqxQXU+ouZFQsZOx50z4=
 gonum.org/v1/gonum v0.17.0/go.mod h1:El3tOrEuMpv2UdMrbNlKEh9vd86bmQ6vqIcDwxEOc1E=
-google.golang.org/adk v1.3.0 h1:paUr9uM2qANnMUAQ4ydMXMCnM1HtymhDYl8y7gnKvqs=
-google.golang.org/adk v1.3.0/go.mod h1:R8tNFnI/eiBXHn7zJPJtqdiK/WXC+tVkyuZsXyNZXN4=
+google.golang.org/adk v1.4.0 h1:Qi4KB9YKD00/I5K9v3QsZ9ng5YiZQ7MfMgM8BZjNcsM=
+google.golang.org/adk v1.4.0/go.mod h1:R8tNFnI/eiBXHn7zJPJtqdiK/WXC+tVkyuZsXyNZXN4=
 google.golang.org/api v0.281.0 h1:sohYgszGGg3zC0P6ncdV6J9IOBtN9LVfFKz8C9tTtJU=
 google.golang.org/api v0.281.0/go.mod h1:6Wssta4c5n9qHq5CBhmlai5h/PUa1djdDAIhYEHyvcM=
 google.golang.org/genai v1.58.0 h1:MNA3ZkRyr7MnRwZ9RNZ60p4+UMKV3yYRw6pyHq4pp0U=