refactor: new apisix ingress controller

[ronething]

Signed-off-by: ashing axingfly@gmail.com

Type of change:

• Bugfix
• New feature provided
• Improve performance
• Backport patches
• Documentation
• Refactor
• Chore
• CI/CD or Tests

What this PR does / why we need it:

ref: https://lists.apache.org/thread/r8ydjz4nq35xokov2lc6sfhppybqwgrn

Pre-submission checklist:

• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

[Copilot]

Pull Request Overview

This PR refactors the documentation for the new APISIX Ingress Controller by removing many outdated files and introducing a new, streamlined structure. Key changes include:

• Removal of numerous legacy documentation files (e.g. tutorials, deployment guides, CRD concepts, contribution and FAQ pages).
• Addition of new documentation files (e.g. Configure and Concepts) to reframe and simplify the user guidance.
• Cleanup of the sidebar configuration by removing the old config.json.

Reviewed Changes

Copilot reviewed 147 out of 742 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
docs/en/latest/monitoring.md	Removed outdated monitoring tutorial.
docs/en/latest/getting-started.md	Removed legacy “Getting Started” guide.
docs/en/latest/design.md	Removed old design documentation.
docs/en/latest/deployments/*	Removed multiple deployment guides (TKE, OpenShift, etc.).
docs/en/latest/contribute.md	Removed obsolete contribution guide.
docs/en/latest/config.json	Removed sidebar configuration file.
docs/en/latest/concepts/*	Removed numerous detailed CRD and concept docs.
docs/crd/config.yaml	Removed CRD config file from documentation.
docs/crd/api.md	Removed large CRD API reference (to be restructured).
docs/configure.md	New file added with APISIX Ingress Controller configuration.
docs/concepts.md	New file added providing a high-level concepts overview.