[fix](fs) Make PathUtils.equalsIgnoreSchemeIfOneIsS3 path comparison consistent

[LuciferYang]

What problem does this PR solve?

Issue Number: close #64767

Problem Summary:

PathUtils.equalsIgnoreSchemeIfOneIsS3(p1, p2) (used by HMSTransaction to decide whether a Hive commit needs a rename) compared paths inconsistently across its two branches:

• same scheme → full-string equalsIgnoreCase (trailing slash significant, case-insensitive);
• cross-scheme with s3 → normalized authority+path via Objects.equals (trailing slash stripped, case-sensitive).

So the result for one URI depended on the other URI's scheme, and same-scheme comparisons wrongly ignored case (S3 keys are case-sensitive).

This PR unifies both branches into one rule: when the schemes are equal (case-insensitively, per RFC 3986 §3.1) or one side is s3, compare only the authority (bucket/host) and path — scheme ignored, trailing slashes insignificant, case-sensitive on the raw (percent-encoded) components; otherwise the locations are not equal. This matches the original normalize() intent and the caller's "no rename when the location is identical" comment, and applies the slash/case handling consistently regardless of whether the two schemes match.

Inputs that are malformed for object storage fall back to exact string comparison so they cannot spuriously match: opaque URIs (s3:bucket/key), scheme-with-null-authority triple-slash forms (s3:///path), authority-with-null-scheme network-path references (//bucket/path), and parse failures. Percent-encoded slashes (%2F) stay distinct from real path separators.

The change was hardened via a multi-persona adversarial review loop run to convergence (5 consecutive clean rounds); the extra rounds mainly added test coverage.

Release note

None

Check List (For Author)

• Test

  • Unit Test (PathUtilsTest, 23 cases covering the consistency contract plus opaque/encoded/triple-slash/network-path/null/scheme-family edge cases)

• Behavior changed:

  • Yes. equalsIgnoreSchemeIfOneIsS3 now treats trailing slashes as insignificant and the authority+path comparison as case-sensitive consistently for same-scheme and cross-scheme inputs. For realistic fully-qualified Hive S3/OSS locations the rename decision is unchanged; the difference only appears for trailing-slash-only or case-only differences and for malformed inputs.

• Does this need documentation?

  • No.

[hello-stephen]

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