debugger: Filter out debug scenarios with invalid Adapters from debug picker (#35744)

I also removed a debug assertion that wasn't true when a debug session
was restarting through a request, because there wasn't a booting task
Zed needed to run before the session.

I renamed SessionState::Building to SessionState::Booting as well,
because building implies that we're building code while booting the
session covers more cases and is more accurate.

Release Notes:

- debugger: Filter out more invalid debug configurations from the debug
picker

Co-authored-by: Remco Smits <djsmits12@gmail.com>

crates/debugger_ui/src/tests/new_process_modal.rs

@@ -298,7 +298,7 @@ async fn test_dap_adapter_config_conversion_and_validation(cx: &mut TestAppConte
 
     let adapter_names = cx.update(|cx| {
         let registry = DapRegistry::global(cx);
-        registry.enumerate_adapters()
+        registry.enumerate_adapters::<Vec<_>>()
     });
 
     let zed_config = ZedDebugConfig {