Refactor/isolate websocket tests

[nicholashanson]

Refactored websocket unit tests from unittest.cpp into unit_tests/test_websocket.cpp

Also made the following small changed:

• Changed one-line http_message string:

  static std::string http_message = "GET /ws HTTP/1.1\r\nConnection: keep-alive, Upgrade\r\nupgrade:...
  

  into multi-line string:

      static std::string http_message = 
        "GET /ws HTTP/1.1\r\n"
        "Connection: keep-alive, Upgrade\r\n"
        "upgrade: websocket\r\n"
        "Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\n"
        "Sec-WebSocket-Version: 13\r\n"
        "Host: localhost\r\n"
        "\r\n";
  

• Added "[websocket]" tag to websocket unit tests so they can be run in isolation.

Before refactor:

Filters: "websocket","websocket_close","websocket_missing_host","websocket_max_payload","websocket_subprotocols","mirror_websocket_subprotocols"
Randomness seeded to: 3072039813
(2025-09-15 22:39:02) [INFO    ] Crow/master server is running at http://127.0.0.1:45451 using 2 threads
...
(2025-09-15 22:39:02) [INFO    ] Closing main IO service (0x7087d0005e88)
(2025-09-15 22:39:02) [DEBUG   ] Connection (0x7087c80043c0) freed, total: 0
(2025-09-15 22:39:02) [INFO    ] Exiting.
===============================================================================
All tests passed (69 assertions in 6 test cases)

After refactor:

Filters: [websocket]
Randomness seeded to: 3659788270
(2025-09-15 22:41:06) [INFO    ] Crow/master server is running at http://127.0.0.1:45471 using 2 threads
...
(2025-09-15 22:41:06) [INFO    ] Closing main IO service (0x7144180051b8)
(2025-09-15 22:41:06) [DEBUG   ] Connection (0x714410005730) freed, total: 0
(2025-09-15 22:41:06) [INFO    ] Exiting.
===============================================================================
All tests passed (69 assertions in 6 test cases)

[gittiver]

please replace globbing by explicit file listing