Fix Gemini Code's (GC) smarts.

- The tl;dr; is that GC couldn't see what the user was saying when tool call events happened in response. The rason why this was happening was because we were instantly invoking tools that the model told us to invoke and then instantly re-requesting. This resulted in the bug because the genai APIs can't update the chat history before a full response has been completed (doesn't know how to update if it's incomplete).
- To address the above issue I had to do quite the large refactor. The gist is that now turns truly drive everything on the server (vs. a server client split). This ensured that when we got tool invocations we could control when/how re-requesting would happen and then also ensure that history was updated. This change also meant that the server would act as an event publisher to enable the client to react to events rather than try and weave in complex logic between the events.
- A BIG change that this changeset incudes is the removal of all of the CLI tools in favor of the server tools.
- Removed some dead code as part of this
- **NOTE: Confirmations are still broken (they were broken prior to this); however, I've set them up to be able to work in the future, I'll dot hat in a follow up to be less breaking to others.**

Fixes https://b.corp.google.com/issues/412320087

packages/server/src/tools/tools.ts

@@ -49,7 +49,14 @@ export interface Tool<
    */
   getDescription(params: TParams): string;
 
-  // Removed shouldConfirmExecute as it's UI-specific
+  /**
+   * Determines if the tool should prompt for confirmation before execution
+   * @param params Parameters for the tool execution
+   * @returns Whether execute should be confirmed.
+   */
+  shouldConfirmExecute(
+    params: TParams,
+  ): Promise<ToolCallConfirmationDetails | false>;
 
   /**
    * Executes the tool with the given parameters
@@ -115,7 +122,17 @@ export abstract class BaseTool<
     return JSON.stringify(params);
   }
 
-  // Removed shouldConfirmExecute as it's UI-specific
+  /**
+   * Determines if the tool should prompt for confirmation before execution
+   * @param params Parameters for the tool execution
+   * @returns Whether or not execute should be confirmed by the user.
+   */
+  shouldConfirmExecute(
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    params: TParams,
+  ): Promise<ToolCallConfirmationDetails | false> {
+    return Promise.resolve(false);
+  }
 
   /**
    * Abstract method to execute the tool with the given parameters
@@ -148,3 +165,27 @@ export type ToolResultDisplay = string | FileDiff;
 export interface FileDiff {
   fileDiff: string;
 }
+
+export interface ToolCallConfirmationDetails {
+  title: string;
+  onConfirm: (outcome: ToolConfirmationOutcome) => Promise<void>;
+}
+
+export interface ToolEditConfirmationDetails
+  extends ToolCallConfirmationDetails {
+  fileName: string;
+  fileDiff: string;
+}
+
+export interface ToolExecuteConfirmationDetails
+  extends ToolCallConfirmationDetails {
+  command: string;
+  rootCommand: string;
+  description: string;
+}
+
+export enum ToolConfirmationOutcome {
+  ProceedOnce,
+  ProceedAlways,
+  Cancel,
+}