Feature/tinacms docs breadcrumbs

[KushalXCoder]

Fixes #4671

General Contributing:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Description

This PR resolves the issue where the documentation breadcrumbs lacked clickable parent paths and simplified the underlying route-matching mechanics.

Acceptance Criteria Checklist (As mentioned in the issue)

• AC 1: Breadcrumbs are displayed on all applicable TinaCMS documentation pages.
• AC 2: Breadcrumbs follow the SSW Design System specifications (aligned with design tokens).
• AC 3: Implementation aligns with approved Figma design.
• AC 4: Breadcrumbs accurately reflect the documentation hierarchy and current page location.
• AC 5: Breadcrumbs are responsive (uses flex-wrap and max-w-full to scale correctly on all screens).
• AC 6: Breadcrumbs meet accessibility standards (semantic <nav>, <ol>, <li> tags, and aria-label="Breadcrumb").
• AC 7: Visual and behavioral consistency is achieved (parents clickable, final item styled as text).

Key Changes

1. Parent Path Navigation: Added recursive searching (getFirstChildSlug) to find the first child page under category folders that do not have their own document, allowing all parent paths to be clickable links.
2. Active Page Display: Disabled links on the active page itself (rendered as a plain <span> element) as per standard UX best practices.
3. Code Standards: Fully formatted with Biome (no unused imports, block braces, and array key checks).

Screenshot of changes

At the top, the breadcrumbs will be visible.

[vercel]

@KushalXCoder is attempting to deploy a commit to the TinaCMS Team on Vercel.

A member of the Team first needs to authorize it.

[CLAassistant]

All committers have signed the CLA.

[KushalXCoder]

@joshbermanssw Can you look at this PR ?