fix(nameserver): reject structurally invalid IPv6 address literals

[yyqdbngt]

Summary

• NamesrvAddrParser.isValidIpv6Literal now performs a full address-literal parse
  (InetAddress.getByName, after the existing character-set pre-filter that prevents
  any DNS lookup) in addition to the character/colon checks.
• Added regression tests: literals with too few groups ([1:2:3], [ffff:0]) are
  rejected, and full-form literals are accepted and lowercased.

Why

The old check only validated the character set and required at least two colons, so
[1:2:3] — three groups, not a valid IPv6 address — was accepted into the registry
and only failed much later when the probe connected through the RocketMQ client. The
pre-filtered character set guarantees getByName treats the value as a literal (no
hostname, no DNS), so the parse adds full structural validation without the
unbounded-resolution risk the parser was designed to avoid.

Testing

• cd server && mvn -Dtest=NamesrvAddrParserTest test — Tests run: 17, Failures: 0, Errors: 0
• cd server && mvn -Dtest=NameserverRegistryServiceTest,NameServerControllerTest test
  — Tests run: 36, Failures: 0, Errors: 0

[RockteMQ-AI]

Summary

Solid fix — the old validation only checked character set + colon count, so [1:2:3] was incorrectly accepted. Using InetAddress.getByName after the character pre-filter is safe (no DNS risk) and provides full structural validation. Good regression tests.

LGTM.

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Automated review by github-manager-bot

[RockteMQ-AI]

Summary

Defensive fix that improves input validation and error handling. Code looks clean and follows existing patterns.

LGTM

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Automated review by "github-manager-bot"

[RockteMQ-AI]

LGTM — defensive fix improving input validation and error handling.

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Automated review by "github-manager-bot"