test: add integration tests for real-time collaboration WebSocket sessions

[mahek-builds]

…sions

Description

Added integration tests for real-time collaboration WebSocket sessions to verify user presence synchronization, name parameter sanitization, and connection/session cleanup.
Specifically, added:

• test_presence_sync_broadcasts_on_join_and_leave: Verifies that presence updates are correctly broadcasted when clients join or disconnect.
• test_presence_sync_handles_name_sanitization: Verifies name defaults (Anonymous), handling of whitespace, and enforcing name length limit constraints (throwing 1008 code).
• test_presence_sync_session_cleanup: Verifies that rooms are deleted and cleanly reset upon user disconnection.

Related Issue

Fixes #

Type of change

• Bug fix
• New feature / enhancement
• Documentation update
• Test addition
• Refactor

Checklist

• I have read CONTRIBUTING.md
• My branch is up to date with main
• I have run pytest -v and all tests pass
• I have not introduced duplicate issues or features
• My PR title follows the format: feat/fix/docs/test: short description
• I have added tests for new features (Level 2 and 3 issues)
• No hardcoded secrets or API keys in my code
• This PR is linked to a GSSoC 2026 issue

Screenshots (if frontend change)

Test evidence

backend/tests/test_collaboration_ws.py::test_collaboration_ws_connection PASSED
backend/tests/test_collaboration_ws.py::test_collaboration_ws_invalid_session PASSED
backend/tests/test_collaboration_code_update_broadcasts PASSED
backend/tests/test_collaboration_multiple_clients PASSED
backend/tests/test_collaboration_invalid_json_message PASSED
backend/tests/test_collaboration_ping_returns_pong PASSED
backend/tests/test_collaboration_ws.py::test_presence_sync_broadcasts_on_join_and_leave PASSED
backend/tests/test_collaboration_ws.py::test_presence_sync_handles_name_sanitization PASSED
backend/tests/test_collaboration_ws.py::test_presence_sync_session_cleanup PASSED

======================= 9 passed, 116 warnings in 5.72s =======================

pytest -v
# paste output

[mahek-builds]

pls review my pr and merge this and give me points for gssoc

[imDarshanGK]

@mahek-builds

[mahek-builds]

@imDarshanGK I fixed the issue

[imDarshanGK]

@mahek-builds

[mahek-builds]

@imDarshanGK I fixed the issue

[imDarshanGK]

@mahek-builds

[mahek-builds]

@imDarshanGK FIXED

[imDarshanGK]

@mahek-builds issue number?