docs: add test maturity model documentation

[johnsongeorge-w]

Description

Introducting Test Maturity model for LISA

Related Issue

Type of Change

• Bug fix
• New feature
• Breaking change
• Refactoring
• Documentation update

Checklist

• Description is filled in above
• No credentials, secrets, or internal details are included
• Peer review requested (if not, add required peer reviewers after raising PR)
• Tests executed and results posted below

Test Validation

Key Test Cases:

N/A
Impacted LISA Features:

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Tested Azure Marketplace Images:

Test Results

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[Copilot]

Pull request overview

This PR adds a new documentation page describing a proposed “Test Maturity Model” concept for LISA test lifecycle/readiness, and links it from the main docs entry points so it’s discoverable.

Changes:

• Added a new docs/test_maturity_model.rst page describing maturity levels and intended selection behavior.
• Linked the new page from docs/index.rst (Sphinx toctree) and from README.rst (hosted docs link).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
README.rst	Adds a link to the published “Test Maturity Model” docs page.
docs/test_maturity_model.rst	Introduces the new Test Maturity Model documentation page.
docs/index.rst	Adds the new page to the Sphinx toctree for navigation.

[LiliDeng]

@johnsongeorge-w Looks good overall. It might be worth adding a bit more detail on a few areas:

Why introduce a dedicated maturity field instead of using tags?
How is precedence handled if both the suite and the test case specify a maturity value?
A simple diagram (or step-by-step description) of the test selection flow, showing how runbook criteria, the implicit stable gate, forceInclude, and forceExclude are applied.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

[johnsongeorge-w]

@johnsongeorge-w Looks good overall. It might be worth adding a bit more detail on a few areas:

Why introduce a dedicated maturity field instead of using tags? How is precedence handled if both the suite and the test case specify a maturity value? A simple diagram (or step-by-step description) of the test selection flow, showing how runbook criteria, the implicit stable gate, forceInclude, and forceExclude are applied.

Updated.