DOCS-1761 - Document self-service feature opt-in for all customers

[JV0812]

Purpose of this pull request

This pull request extends the existing MSSP-only "Manage Features" self-service opt-in/opt-out capability to all customers managing their own organization (not just child orgs), per DOCS-1761. It also removes references to sub-feature management, which is not currently supported.

• Adds a new Manage features section to manage-org-settings.md, covering opt-in/opt-out for your own organization.
• Removes the two sub-features references from manage-orgs-for-mssps.md.
• Updates mobot.md's "Opting out" section and the AI/ML FAQ to point to self-service opt-out where available.

Select the type of change

• Minor Changes - Typos, formatting, slight revisions
• Update Content - Revisions, updating sections
• New Content - New features, sections, pages, tutorials
• Site and Tools - .clabot, version updates, maintenance, dependencies, new packages for the site (Docusaurus, Gatsby, React, etc.)

Ticket (if applicable)

https://sumologic.atlassian.net/browse/DOCS-1761

[JV0812]

@ndhar-sumo Question on sub-feature management in the Manage Features panel, since it affects both this PR and #6979.

This PR originally removed the two "sub-features" references from manage-orgs-for-mssps.md (and didn't add them to the new self-service section in manage-org-settings.md), on the assumption that sub-feature management isn't currently supported:

• "Some features include sub-features. You can expand a top-level feature to manage its sub-features individually."
• "To manage sub-features, click the feature name to expand it and select the desired sub-features."

But #6979 touches the same section of manage-orgs-for-mssps.md and leaves those lines untouched, so I've restored them here rather than ship a contradiction between the two PRs.

Can you confirm: does the Manage Features panel currently support managing sub-features (expand a feature to toggle sub-features individually), or was that description stale/inaccurate to begin with? Want to get this right before either PR merges.

[ndhar-sumo]

before

There are no sub-features under a feature, so we need to remove all mentions of that.

[kimsauce]

Hi @JV0812 , just letting you know I caught and fixed something I'd missed in docs/get-started/ai-machine-learning.md (unrelated to your PR) and made sure not to overwrite your changes.

[kimsauce]

Two things from review that aren't part of the merge conflict (now resolved) but are worth fixing before this merges:

1. "child organizations" wording in the new Manage features section (manage-org-settings.md): the intro says "you can manage feature availability for your child organizations," but this section is meant to cover self-service opt-in/opt-out for your own organization — that's the point of this PR (extending the capability beyond MSSP/child-org management, which is already documented in manage-orgs-for-mssps.md). Looks like it may have been copy-pasted from that MSSP doc without adjusting the audience.

2. Sub-feature references not removed from manage-orgs-for-mssps.md: the PR description says this PR "removes the two sub-features references from manage-orgs-for-mssps.md," but that file isn't in the diff. The references are still on main at lines 45 and 57 ("Some features include sub-features..." / "To manage sub-features, click the feature name to expand it..."). Either that change didn't make it into this branch, or the description is out of date — worth double-checking before merge since it describes a capability that (per this PR) isn't supported.