feature: not always open new window

[HairlessVillager]

在之前的版本中，web_search和export_file工具会总是打开新窗口，这个 PR 修改了一部分代码，让着两个工具可以在已有的窗口进行操作。

这个 PR 还对Eko类增加了一个可选的ekoConfig参数，其中的alwaysOpenNewWindow字段可以决定是否总是在新窗口打开。

然而，当我尝试把代码加载到浏览器插件时出现了问题。当我尝试 prompt Search Sam Altman's information and summarize it into markdown format for export时，在 popup 窗口的 console 总是会在开头打印ekoConfig: undefined。这看起来是Eko.constructor()打印的，提示浏览器插件的相关代码在调用 Eko 框架时出现了不兼容的情况。

由于我对于浏览器插件的代码并不熟悉，所以请求对这块业务熟悉的人拉取这个 PR 的代码进行调试。

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In previous versions, the web_search and export_file tools would always open new windows. This pull request (PR) modifies part of the code to allow these two tools to operate within existing windows.

Additionally, this PR introduces an optional ekoConfig parameter to the Eko class, which includes an alwaysOpenNewWindow field that determines whether to always open a new window.

However, issues arose when I tried to load the code into the browser extension. When I attempted to prompt with "Search Sam Altman's information and summarize it into markdown format for export," the console in the popup window always printed ekoConfig: undefined at the beginning. It seems that this was printed by Eko.constructor(), suggesting an incompatibility in the browser extension's relevant code when calling the Eko framework.

Since I am not familiar with the code for browser extensions, I request that someone who is familiar with this area pull the code for this PR and debug it.

[HairlessVillager]

请求对这块业务熟悉的人拉取这个 PR 的代码进行测试。如果已经测试了，请把结果发给我，只有测试通过了这个 PR 才可以被合并。

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Please ask someone familiar with this business to pull the code of this pull request (PR) for testing. If it has already been tested, please send me the results. Only after the PR passes the test can it be merged.