refactor(browser-tools): require explicit tab targets

Remove hidden active-browser targeting so automation requests carry workspace in the envelope and browserId in tab command args.

packages/desktop/src/main.ts

@@ -56,7 +56,6 @@ import {
   registerBrowserWebviewNavigationGuards,
   registerPaseoBrowserWorkspace,
   registerPaseoBrowserWebContents,
-  setAgentActivePaseoBrowserId,
   setWorkspaceActivePaseoBrowserId,
 } from "./features/browser-webviews/index.js";
 import { parseOpenProjectPathFromArgv } from "./open-project-routing.js";
@@ -144,20 +143,6 @@ function readActiveBrowserInput(
   return { workspaceId: record.workspaceId.trim(), browserId: browserId || null };
 }
 
-function readAgentActiveBrowserInput(
-  input: unknown,
-): { agentId: string; browserId: string | null } | null {
-  if (typeof input !== "object" || input === null || Array.isArray(input)) {
-    return null;
-  }
-  const record = input as Record<string, unknown>;
-  if (typeof record.agentId !== "string" || record.agentId.trim().length === 0) {
-    return null;
-  }
-  const browserId = typeof record.browserId === "string" ? record.browserId.trim() : null;
-  return { agentId: record.agentId.trim(), browserId: browserId || null };
-}
-
 const pendingBrowserWebviewIds: string[] = [];
 
 function isBrowserRefreshInput(input: Electron.Input): boolean {
@@ -350,13 +335,6 @@ ipcMain.handle("paseo:browser:set-workspace-active-browser", (_event, rawInput:
   }
 });
 
-ipcMain.handle("paseo:browser:set-agent-active-browser", (_event, rawInput: unknown) => {
-  const input = readAgentActiveBrowserInput(rawInput);
-  if (input) {
-    setAgentActivePaseoBrowserId(input);
-  }
-});
-
 ipcMain.handle("paseo:browser:open-devtools", (_event, browserId: unknown) => {
   if (typeof browserId !== "string" || browserId.trim().length === 0) {
     const result = {