Add Sampling Configuration Actions

[seanzatzdev]

This PR adds the action classes associated with setting, getting, and deleting Sampling Configurations.

Set Configuration
The set configuration API structure will be similar to the following:

PUT /<index-name>/_sample/config
{
  "rate": "5%", // required
  "max_samples": 20 // optional, buffer size, defaults to 10
  "max_size": 10mb, // optional, max size of documents, defaults to 1mb
  "time_to_live": 1d, // optional, time after which documents may be deleted, defaults to never
  "if": "ctx?.network?.name == 'Guest'" // optional, same syntax as pipeline conditional
}

Get Configuration
The GET //_sample/config API will get a specific configuration. For example:

GET /logs/_sample/config
[
  {
    "index": "logs",
    "configuration:
    {
      "rate": "5%",
      "if": "ctx?.network?.name == 'Guest'"
    }
  }
]

An API to get all currently-configured APIs will also be provided:

GET /_sample/config
[
  {
    "index": "logs",
    "configuration:
    {
      "rate": "5%",
      "if": "ctx?.network?.name == 'Guest'"
    }
  },
  {
    "index": "my-index",
    "configuration:
    {
      "rate": "25%"
    }
  }
]

Delete Configuration
A delete API, DELETE //_sample/config, will remove the sampling configuration for the given index or data stream and cleans up any associated in-memory storage.

[Copilot]

Pull Request Overview

This PR introduces action classes for managing sampling configuration in Elasticsearch, specifically adding PutSamplingConfigurationAction and associated functionality for configuring sampling settings on indices.

• Adds PutSamplingConfigurationAction class with request/response handling for sampling configuration
• Implements comprehensive test coverage for the new action including serialization, mutation testing, and validation
• Provides API for configuring sampling parameters like rate, max samples, size limits, TTL, and conditions

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
PutSamplingConfigurationAction.java	Main action class implementing sampling configuration functionality with request handling, serialization, and task creation
PutSamplingConfigurationActionTests.java	Comprehensive test suite covering serialization, mutation testing, and action validation

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[Copilot]

Pull Request Overview

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

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[Copilot]

Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

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