Pull diagnostics fixes (#32242)

Follow-up of https://github.com/zed-industries/zed/pull/19230

* starts to send `result_id` in pull requests to allow servers to reply
with non-full results
* fixes a bug where disk-based diagnostics were offset after pulling the
diagnostics
* fixes a bug due to which pull diagnostics could not be disabled
* uses better names and comments for the workspace pull diagnostics part

Release Notes:

- N/A

assets/settings/default.json

@@ -1033,9 +1033,14 @@
     "button": true,
     // Whether to show warnings or not by default.
     "include_warnings": true,
-    // Minimum time to wait before pulling diagnostics from the language server(s).
-    // 0 turns the debounce off, `null` disables the feature.
-    "lsp_pull_diagnostics_debounce_ms": 50,
+    // Settings for using LSP pull diagnostics mechanism in Zed.
+    "lsp_pull_diagnostics": {
+      // Whether to pull for diagnostics or not.
+      "enabled": true,
+      // Minimum time to wait before pulling diagnostics from the language server(s).
+      // 0 turns the debounce off.
+      "debounce_ms": 50
+    },
     // Settings for inline diagnostics
     "inline": {
       // Whether to show diagnostics inline or not