HDDS-15081. Add Internal Scaffold

[henrybear327]

What changes were proposed in this pull request?

Introduce ozone local command skeleton.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-15081

How was this patch tested?

With unit test.

[Copilot]

Pull request overview

Introduces an internal, hidden ozone local CLI scaffold to support future local single-node Ozone runtime commands.

Changes:

• Adds OzoneLocal CLI entrypoint with a hidden run placeholder subcommand.
• Introduces a LocalOzoneRuntime interface defining the local runtime contract.
• Adds unit tests verifying picocli metadata and help output behavior for the new command.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/local/OzoneLocal.java	Adds the hidden ozone local command skeleton and hidden run placeholder subcommand.
hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/local/LocalOzoneRuntime.java	Defines a runtime contract interface for future local single-node runtime implementations.
hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/local/package-info.java	Introduces package-level documentation for the new org.apache.hadoop.ozone.local package.
hadoop-ozone/tools/src/test/java/org/apache/hadoop/ozone/local/TestOzoneLocal.java	Adds unit tests for command metadata, subcommand registration, and help output hiding behavior.

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[Copilot]

The assertion assertFalse(help.contains("run")) is fairly broad and can become brittle if the root help text later includes the substring "run" for unrelated reasons (eg, wording like "running" / "runtime" in a description or option). Consider tightening this to check for a subcommand listing entry (eg, a line/section that specifically enumerates subcommands) or asserting via picocli metadata that the hidden subcommand is not rendered in the usage output.

Suggested change

	assertEquals(0, exitCode);
	assertTrue(help.contains("Usage: ozone local"));
	assertFalse(help.contains("run"));
	boolean runSubcommandListed = help.lines()
	.map(String::stripLeading)
	.anyMatch(line -> line.equals("run")
	|| line.startsWith("run ")
	|| line.startsWith("run\t"));
	assertEquals(0, exitCode);
	assertTrue(help.contains("Usage: ozone local"));
	assertFalse(runSubcommandListed);

[peterxcli]

LGTM

[peterxcli]

Thanks @henrybear327 for the patch, @ivandika3 for creating the label!