feat(video): Add the list connections response

[dragonmantank]

See title

Contribution Checklist

• Unit tests!
• Updated CHANGELOG.md
• My name is in CONTRIBUTORS.md

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.93%. Comparing base (c5c0999) to head (d0b8b37).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #610   +/-   ##
=========================================
  Coverage     98.93%   98.93%           
- Complexity     3610     3622   +12     
=========================================
  Files           542      545    +3     
  Lines          7987     8004   +17     
  Branches        443      443           
=========================================
+ Hits           7902     7919   +17     
  Misses           64       64           
  Partials         21       21           

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[Copilot]

Pull request overview

This PR adds support for listing connections in Vonage Video sessions. The implementation follows the established patterns in the video package and includes comprehensive test coverage.

Changes:

• Added listConnections() method to VideoClient to retrieve all connections from a video session
• Created Connection class to represent individual connection data
• Created ConnectionState enum to represent connection states (CONNECTING, CONNECTED, DISCONNECTED)
• Created ListConnectionsResponse class to wrap the API response
• Added comprehensive test coverage including unit tests and endpoint tests

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/main/java/com/vonage/client/video/VideoClient.java	Added listConnections endpoint and public method
src/main/java/com/vonage/client/video/ListConnectionsResponse.java	Response model extending ListResourceResponse with projectId and sessionId fields
src/main/java/com/vonage/client/video/Connection.java	Entity class representing a connection with id, state, and creation timestamp
src/main/java/com/vonage/client/video/ConnectionState.java	Enum defining connection states with custom capitalization pattern
src/test/java/com/vonage/client/video/VideoClientTest.java	Added test methods and loadJsonResource helper for testing list connections functionality
src/test/java/com/vonage/client/video/ListConnectionsResponseTest.java	Comprehensive tests for ListConnectionsResponse deserialization
src/test/resources/com/vonage/client/video/list-connections-response.json	Test fixture with sample connection data
src/test/resources/com/vonage/client/video/list-connections-response-full.json	Test fixture with placeholders for parameterized testing
CHANGELOG.md	Updated with new feature entry

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[Copilot]

@dragonmantank I've opened a new pull request, #611, to work on those changes. Once the pull request is ready, I'll request review from you.