[backport/v0.41.x] docs: Remove deprecated "Interfaces" section (#8294)

[amaury1093]

backports #8294

• Remove useless files, add app.toml section

• Rework docs

• Delete interfaces

• add correct next section references

• Finish CLI

• Small tweaks query

• Add simulation docs to core

• Add gRPC and REST

• Finish queyr lifecycle

• Updat examples

• Remove prereq

• fix links in simulation

• Use same enumeration in md

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Description

closes: #XXXX

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• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes