docs: Added Control Plane architecture diagram in Concepts page

[nthapa000]

What this PR does:
Adds Control Plane architecture diagram in Concepts page

Why we need it:
For better Control Plane architecture overview in v0.57.x

Which issue(s) this PR fixes:

Fixes #7042

v0.57.x

v1.0.x

Does this PR introduce a user-facing change?:

• How are users affected by this change: Not directly, a documentation change
• Is this breaking change: No
• How to migrate (if breaking change):

[github-actions]

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[nthapa000]

I have currently added the Control Plane Architecture diagram to the v1.0.x documentation also. However, I'm a little doubtful about whether I should keep it, since there's already a link that redirects users to the Control Plane Architecture Overview.

[Ayushmore1214]

Looks like an good approach to me! @rahulshendre thoughts ?

[rahulshendre]

@nthapa000, you were definitely attentive during the newcomers meet 🙌

[rahulshendre]

Overall LGTM, just copy it to docs dev as well
docs-dev is the working copy that becomes the next v0 release, or it'll be lost on the next v0 release

It doesn't overlap with the link, the diagram gives a quick visual on the concepts page, while the linked page goes deeper with the per-component breakdown, so they serve different purposes and the link is relevant.
I also pulled it locally and it renders cleanly on both v0.57.x and v1.0.x

[nthapa000]

Overall LGTM, just copy it to docs dev as well docs-dev is the working copy that becomes the next v0 release, or it'll be lost on the next v0 release

It doesn't overlap with the link, the diagram gives a quick visual on the concepts page, while the linked page goes deeper with the per-component breakdown, so they serve different purposes and the link is relevant. I also pulled it locally and it renders cleanly on both v0.57.x and v1.0.x

Thanks @rahulshendre for feedback, added in docs-dev

[rahulshendre]

LGTM 👍🏻
Thanks @nthapa000