fix(browser): change default wait_until from load to domcontentloaded

[OhYee]

Updated the default wait_until parameter from 'load' to 'domcontentloaded' for browser navigation functions to improve performance and reduce waiting time for full page loads when not necessary.

This change affects browser_navigate_back and browser_go_forward functions in the BrowserToolSet class to use 'domcontentloaded' as the default waiting strategy instead of 'load'.

将默认的 wait_until 参数从 'load' 更改为 'domcontentloaded'

更新了浏览器导航函数的默认 wait_until 参数，从 'load' 改为 'domcontentloaded' 以提高性能并减少不必要的完整页面加载等待时间。

此更改影响 BrowserToolSet 类中的 browser_navigate_back 和
browser_go_forward 函数，使用 'domcontentloaded' 作为默认等待策略 而不是 'load'。

fix #66

Change-Id: Ib5d4120869bfea9ea8a411b16958bf9359572b9f

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[Copilot]

Pull request overview

This pull request updates BrowserToolSet’s browser history navigation defaults to wait for domcontentloaded instead of load, reducing unnecessary wait time on back/forward navigations.

Changes:

• Change browser_navigate_back default wait_until from "load" to "domcontentloaded".
• Change browser_go_forward default wait_until from "load" to "domcontentloaded".
• Minor formatting adjustments in _get_playwright logging/conditionals.

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[Copilot]

The PR description references fixing issue #66, but the code change here only updates the default wait_until value for back/forward navigation. Please either update the PR description/issue reference to match the actual change, or include the missing code changes intended to address #66.

[Copilot]

This PR changes behavior by altering the default wait_until for browser_navigate_back/browser_go_forward, but there are no unit tests asserting the new defaults. Consider adding a small test (e.g., via inspect.signature) to lock in the new default and prevent accidental regressions.