Enhance Connection Pool Configuration: Add min/max Query Parameters, Update Docs, and Refactor Codebase

[ghost]

This pull request introduces enhancements to NodePass's connection pool configuration, updates documentation to reflect these changes, and refactors the codebase to support the new functionality. The most notable changes include adding query parameters for connection pool capacity, updating documentation in both English and Chinese, and modifying the code to handle the new parameters.

Documentation Updates:

• Updated README.md and README_zh.md to include examples of the new min and max query parameters for connection pool configuration. Added a new tool, NodePanel, to the list of NodePass-related projects. [1] [2] [3] [4]
• Added detailed descriptions of the min and max parameters for connection pool capacity in docs/en/configuration.md and docs/zh/configuration.md. Updated environment variable recommendations to align with the new query parameters. [1] [2] [3] [4] [5] [6]
• Enhanced docs/en/usage.md and docs/zh/usage.md to include syntax and examples for the new query parameters in client mode. [1] [2] [3] [4] [5] [6]

Codebase Changes:

• Introduced minPoolCapacity and maxPoolCapacity fields in the Client struct within internal/common.go to store the new parameters.
• Updated the NewClient function in internal/client.go to parse and set the min and max values from the URL.
• Refactored the connection pool initialization in internal/client.go to use the new minPoolCapacity and maxPoolCapacity fields. [1] [2]

These changes improve the flexibility of connection pool configuration, making NodePass more adaptable to various performance and resource constraints.