Make VAMC detail page ToC dependent on two h2s, instead of opt-in

[kevwalsh]

User Story or Problem Statement

VAMC editors can currently choose whether or not to include a table of contents on VAMC detail pages, using this checkbox.

When this component is used incorrectly by a VAMC editor (there are not h2s on the page, in some cases because the editor has added only h3s) the design system component shows an "On this page" header, with no links.

This is a known issue that will not be resolved at the design system component level https://github.com/department-of-veterans-affairs/va.gov-team/issues/28249#.

There are a half dozen content types / page templates in the VAMC product for which the ToC is not optional.

This task is to make the VAMC detail page ToC dependent on the existence of two h2s, and removing the the option for editors.

Acceptance Criteria

• [ ] Only display the ToC if there are two h2s.
• [ ] Consider: adding other criteria, like a character count. (is that technically feasible?)

Implementation steps

## Design principles Veteran-centered - [ ] `Single source of truth`: Increase reliability and consistency of content on VA.gov by providing a single source of truth. - [x] `Accessible, plain language`: Provide guardrails and guidelines to ensure content quality. - [ ] `Purposely structured content`: Ensure Content API can deliver content whose meaning matches its structure. - [ ] `Content lifecycle governance`: Produce tools, processes and policies to maintain content quality throughout its lifecycle. Editor-centered - [ ] `Purpose-driven`: Create an opportunity to involve the editor community in VA’s mission and content strategy goals. - [ ] `Efficient`: Remove distractions and create clear, straightforward paths to get the job done. - [ ] `Approachable`: Offer friendly guidance over authoritative instruction. - [ ] `Consistent`: Reduce user’s mental load by allowing them to fall back on pattern recognition to complete tasks. - [ ] `Empowering`: Provide clear information to help editors make decisions about their work. ### CMS Team Please check the team(s) that will do this work. - [ ] `Program` - [ ] `Platform CMS Team` - [ ] `Sitewide Crew` - [ ] `⭐️ Sitewide CMS` - [ ] `⭐️ Public Websites` - [x] `⭐️ Facilities` - [ ] `⭐️ User support`

[davidmpickett]

This issue was surfaced again: https://dsva.slack.com/archives/C0FQSS30V/p1673645534388259

[laflannery]

I would want this done other places this is used as well. 2 of those places are Benefits Detail pages and Resources and Support pages, both of which are PW products. Because this crosses both teams, is this a CMS issue OR is this actually something that has to be done per template/content type so I should make a ticket for PW for their products?

[mmiddaugh]

@laflannery can you give this a defect level to assist with prioritization, please?