Logging does not display structured log details if a message exceeds certain amount of symbols

I log results from my service calls using `dart:developer.log`. From my assumption, `DevTools` fails to display structured log details whenever message of a log exceeds certain amount of symbols.

Smaller logs are displayed as expected, with details presented:

However, if I try to log JWT token (1391 symbols) , the `Details` section will display just the message string

首先，在 DevTools 中使用 dart:developer.log，通过结构化消息重现问题，该消息长度超过报告的 1,391 个符号，然后将其与较短的日志进行比较。跟踪日志记录和 Details 显示路径，以找出较长消息在何处丢失其结构化数据。当超过报告长度的消息仍能显示结构化日志详情时，即视为完成。

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