Add runnable env support.

editors/code/src/config.ts

@@ -5,6 +5,8 @@ export type UpdatesChannel = "stable" | "nightly";
 
 export const NIGHTLY_TAG = "nightly";
 
+export type RunnableEnvCfg = Record<string, string> | [{ mask?: string, env: Record<string, string>; }]
+
 export class Config {
     readonly extensionId = "matklad.rust-analyzer";
 
@@ -114,6 +116,10 @@ export class Config {
         return this.get<string | undefined>("cargoRunner");
     }
 
+    get runnableEnv() {
+        return this.get<RunnableEnvCfg | undefined>("runnableEnv");
+    }
+
     get debug() {
         // "/rustc/<id>" used by suggestions only.
         const { ["/rustc/<id>"]: _, ...sourceFileMap } = this.get<Record<string, string>>("debug.sourceFileMap");