debugger: Relax implementation of validate_config to not run validation (#31785)

When we moved to schema-based debug configs, we've added validate_config
- a trait method
that is supposed to both validate the configuration and determine
whether it is a launch configuration
or an attach configuration.

The validation bit is a bit problematic though - we received reports on
Discords about
scenarios not starting up properly; it turned out that Javascript's
implementation was overly strict.
Thus, I got rid of any code that tries to validate the config - let's
let the debug adapter itself
decide whether it can digest the configuration or not. validate_config
is now left unimplemented for most
DebugAdapter implementations (except for PHP), because all adapters use
`request`: 'launch'/'attach' for that.
Let's leave the trait method in place though, as nothing guarantees this
to be true for all adapters.

cc @Anthony-Eid

Release Notes:

- debugger: Improved error messages when the debug scenario is not
valid.
- debugger: Fixed cases where valid configs were rejected.

crates/dap_adapters/src/codelldb.rs

@@ -1,11 +1,8 @@
 use std::{collections::HashMap, path::PathBuf, sync::OnceLock};
 
-use anyhow::{Context as _, Result, anyhow};
+use anyhow::{Context as _, Result};
 use async_trait::async_trait;
-use dap::{
-    StartDebuggingRequestArgumentsRequest,
-    adapters::{DebugTaskDefinition, latest_github_release},
-};
+use dap::adapters::{DebugTaskDefinition, latest_github_release};
 use futures::StreamExt;
 use gpui::AsyncApp;
 use serde_json::Value;
@@ -37,7 +34,7 @@ impl CodeLldbDebugAdapter {
                 Value::String(String::from(task_definition.label.as_ref())),
             );
 
-        let request = self.validate_config(&configuration)?;
+        let request = self.request_kind(&configuration)?;
 
         Ok(dap::StartDebuggingRequestArguments {
             request,
@@ -89,48 +86,6 @@ impl DebugAdapter for CodeLldbDebugAdapter {
         DebugAdapterName(Self::ADAPTER_NAME.into())
     }
 
-    fn validate_config(
-        &self,
-        config: &serde_json::Value,
-    ) -> Result<StartDebuggingRequestArgumentsRequest> {
-        let map = config
-            .as_object()
-            .ok_or_else(|| anyhow!("Config isn't an object"))?;
-
-        let request_variant = map
-            .get("request")
-            .and_then(|r| r.as_str())
-            .ok_or_else(|| anyhow!("request field is required and must be a string"))?;
-
-        match request_variant {
-            "launch" => {
-                // For launch, verify that one of the required configs exists
-                if !(map.contains_key("program")
-                    || map.contains_key("targetCreateCommands")
-                    || map.contains_key("cargo"))
-                {
-                    return Err(anyhow!(
-                        "launch request requires either 'program', 'targetCreateCommands', or 'cargo' field"
-                    ));
-                }
-                Ok(StartDebuggingRequestArgumentsRequest::Launch)
-            }
-            "attach" => {
-                // For attach, verify that either pid or program exists
-                if !(map.contains_key("pid") || map.contains_key("program")) {
-                    return Err(anyhow!(
-                        "attach request requires either 'pid' or 'program' field"
-                    ));
-                }
-                Ok(StartDebuggingRequestArgumentsRequest::Attach)
-            }
-            _ => Err(anyhow!(
-                "request must be either 'launch' or 'attach', got '{}'",
-                request_variant
-            )),
-        }
-    }
-
     fn config_from_zed_format(&self, zed_scenario: ZedDebugConfig) -> Result<DebugScenario> {
         let mut configuration = json!({
             "request": match zed_scenario.request {