Support multi-value query parameters

[kwondh5217]

Motivation:

This PR is a follow-up to #6072, which added support for mapping all query parameters into a Map<String, String>. However, it does not handle cases where multiple values exist for the same query parameter key.

For example:

GET /foo?a=1&a=2&b=3

The current implementation only retains the last value a=2, losing a=1.
To better support multi-value query parameters, we introduce support for Map<String, List<?>>.

Modifications:

• Enhanced ofQueryParamMap in AnnotatedValueResolver to support:
  • Map<String, String> → Single-value mapping (existing behavior).
  • Map<String, List> → Multi-value mapping (new behavior).
• If the value type of the map is List<?>, query parameters with the same key are collected into a list.
• Added validation to ensure that the value type is List<?>. If an unsupported type is used, an IllegalArgumentException is thrown.

Result:

• Users can now use @param Map<String, List<?>> to collect multi-value query parameters.

[github-actions]

🔍 Build Scan® (commit: d7daa0d)

Job name	Status	Build Scan®
build-ubicloud-standard-16-jdk-8	✅	https://ge.armeria.dev/s/ealyzhnaayzfg
build-ubicloud-standard-16-jdk-21-snapshot-blockhound	✅	https://ge.armeria.dev/s/x5t4zvwb2tyae
build-ubicloud-standard-16-jdk-17-min-java-17-coverage	❌ (failure)	https://ge.armeria.dev/s/fg4nw3jomsa5s
build-ubicloud-standard-16-jdk-17-min-java-11	✅	https://ge.armeria.dev/s/zcurorri4lfna
build-ubicloud-standard-16-jdk-17-leak	✅	https://ge.armeria.dev/s/qefd4cjsuludi
build-ubicloud-standard-16-jdk-11	✅	https://ge.armeria.dev/s/e66kfgzbr7kyw
build-macos-latest-jdk-21	✅	https://ge.armeria.dev/s/bdsbkdwyunfii

[minwoox]

Left small suggestions. Thanks!

[kwondh5217]

Thanks for the suggestions, @minwoox!
I’ve pushed the updates now.