debugger: Kill debug sessions on app quit (#33273)

Before this PR force quitting Zed would leave hanging debug adapter
processes and not allow debug adapters to clean up their sessions
properly.

This PR fixes this problem by sending a disconnect/terminate to all
debug adapters and force shutting down their processes after they
respond.

Co-authored-by: Cole Miller \<cole@zed.dev\>

Release Notes:

- debugger: Shutdown and clean up debug processes when force quitting
Zed

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>
Co-authored-by: Remco Smits <djsmits12@gmail.com>

.zed/debug.json

@@ -2,11 +2,23 @@
   {
     "label": "Debug Zed (CodeLLDB)",
     "adapter": "CodeLLDB",
-    "build": { "label": "Build Zed", "command": "cargo", "args": ["build"] }
+    "build": {
+      "label": "Build Zed",
+      "command": "cargo",
+      "args": [
+        "build"
+      ]
+    }
   },
   {
     "label": "Debug Zed (GDB)",
     "adapter": "GDB",
-    "build": { "label": "Build Zed", "command": "cargo", "args": ["build"] }
-  }
+    "build": {
+      "label": "Build Zed",
+      "command": "cargo",
+      "args": [
+        "build"
+      ]
+    }
+  },
 ]