HDDS-16139. Define and enforce OFS and O3FS IPv6 authority contracts

[echonesis]

What changes were proposed in this pull request?

This PR defines and enforces the supported IPv6 authority forms for OFS and O3FS following the URI parser changes in HDDS-15775.

• Allow OFS authorities containing bracketed IPv6 literals, with or without an explicit port, such as ofs://[2001:db8::10]:9862/.
• Reject all unbracketed IPv6 authorities in OFS with an error explaining that IPv6 literals must be enclosed in brackets.
• Reject raw IPv6 literals in O3FS authorities with an error recommending an OM service ID or DNS name.
• Preserve existing O3FS forms using bucket.volume, DNS names, IPv4 addresses, and OM service IDs.
• Preserve support for o3fs://bucket.volume/ when the OM endpoint is supplied through configuration, including a configured bracketed IPv6 address.
• Construct OM RPC addresses through the existing bracket-aware host-and-port helper so configured IPv6 addresses retain the required brackets.
• Add coverage for URI construction, filesystem initialization, authority parsing, rejection behavior, configured IPv6 endpoints, and qualified-path round trips.

A dotted O3FS authority cannot contain a bracketed IPv6 literal such as bucket.volume.[2001:db8::10], because java.net.URI rejects that form before O3FS initialization. Therefore, O3FS requires a DNS name or OM service ID when an IPv6 endpoint must be represented in the dotted authority.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-16139

How was this patch tested?

Local Test

mvn -pl :ozone-filesystem-common -am test \
  -Dtest=TestBasicOzoneFileSystems,TestOmUtils,TestOMFailoverProxyProvider \
  -Dsurefire.failIfNoSpecifiedTests=false \
  -DskipShade -DskipRecon -DskipDocs

GitHub Actions CI: https://github.com/echonesis/ozone/actions/runs/32799667939

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