feat: add weekly contest 480

[yanglbme]

No description provided.

[Copilot]

Pull request overview

This PR adds Weekly Contest 480 entries to the LeetCode solutions repository, including four new problems with links to their respective solutions in both English and Chinese documentation. Additionally, it includes minor formatting improvements across several README files.

• Adds 4 new problems from Weekly Contest 480 (problems 3774-3777) to the main problem index
• Creates contest entries in both English and Chinese contest documentation
• Applies spacing/formatting improvements to various README files

Reviewed changes

Copilot reviewed 48 out of 95 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
solution/README_EN.md	Adds 4 new problem entries for Weekly Contest 480 in the English problem index
solution/README.md	Adds 4 new problem entries for Weekly Contest 480 in the Chinese problem index
solution/JAVASCRIPT_README.md	Fixes spacing in header ("JavaScript专项练习" → "JavaScript 专项练习")
solution/DATABASE_README.md	Adds proper spacing to Chinese text in multiple problem titles (e.g., "第N高" → "第 N 高")
solution/CONTEST_README_EN.md	Creates new Weekly Contest 480 section with problem list in English
solution/CONTEST_README.md	Creates new Weekly Contest 480 section with metadata (date: 2025-12-14, duration: 90 min, participants: 1772)
package.json	Downgrades prettier from version 3.4.2 to 3.3.2
README.md	Fixes spacing in list formatting (removes extra spaces before list items) and adds space before tilde in "☕️～"

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