[Feature] Introduces Centralized Resource Access Control and Sharing

[DarshitChanpura]

Description

Introduces a new authorization mechanism to control access to resources defined by plugins.
There are 4 major components to this PR:

1. Introduces an SPI that defines the contracts for a resource sharing plugin as well as Resource Access Control plugin.
2. Introduces 4 new APIs that expose resource-sharing and access verification capabilities.
3. Modifies DLS to implicitly check for resource-access for requesting user if incoming request is for a resource
4. Adds a sample resource plugin with tests to demonstrate the usage of this new feature.
5. Adds a feature flag to toggle the feature. Feature is enabled by default.

• Category : New feature
• Why these changes are required?
  • At present, plugins have implemented in-house authorization mechanisms for a lack of centralized framework. This PR introduces a centralized way to offload resource permissions check to security plugin. Plugins will leverage the java APIs introduced in core.

Issues Resolved

• Related to [Proposal] Resource Permissions and Sharing #4500

Testing

• automated and manual testing

Check List

• New functionality includes testing
• New functionality has been documented
• New Roles/Permissions have a corresponding security dashboards plugin PR
• API changes companion pull request created
• Commits are signed per the DCO using --signoff

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[DarshitChanpura]

I will be adding concrete java doc and update any stale docs soon.

[DarshitChanpura]

I have pushed the final changes with updated documentation.

I've also documented the final changes here: #4500 (comment)

A detailed README is added for plugin devs here: https://github.com/opensearch-project/security/blob/4ba46a13342db50251d2cc0a5d250d6949ff68f5/RESOURCE_ACCESS_CONTROL_FOR_PLUGINS.md