Fix palindrome substring end index, correct length variable, and improve majority-element test

[Etherstrings]

Motivation

• Correct incorrect substring end handling in the longest-palindrome implementation so returned results match expected inclusive end indexing.
• Fix a spelling/variable-name issue in the squared-length helper to improve clarity.
• Reduce space usage of the majority-element routine to O(1) and add runtime assertions to strengthen the test coverage.

Description

• Updated L5_LongestHuiwen.longestPalindrome to use maxLength (renamed from maxlenght) and return s.substring(left, right + 1) so the end index is inclusive.
• Fixed a typo in L593.length by renaming lenght to length and returning the computed length.
• Replaced a HashMap-based majority counting in Test1.getShowMoreN with the Boyer–Moore majority vote algorithm and added occurrence verification; added assertion-based test cases in Test1.main to validate behavior for several inputs.

Testing

• No automated test suite was run in this patch; only assertion-based checks were added to src/Test/Test1.java for local verification at runtime.

---

Codex Task