Pro turns into Mentorship: unify CTAs, rename /pro, reorder nav

[mre]

Summary

Reframes the individual offering from "corrode pro" to Mentorship, unifies the scattered blog call-to-actions into one consistent component, and tidies up the navigation.

The goal: make the site a clearer one-stop-shop for both teams (Consulting) and individuals (Mentorship), without confusing visitors or diluting the team-focused SEO.

What's in here

1. /pro -> /mentorship

• Renamed the route (content/pro/ -> content/mentorship/) with aliases = ["pro"] so old links redirect.
• Consistent labels everywhere: nav, footer, services page, and the new CTA all say "Mentorship" -> /mentorship (no more "Pro Rust Mentorship" / "corrode pro" drift).
• Renamed internal files to match: templates/pro.html -> mentorship.html, sass/_pro.scss -> _mentorship.scss.

2. Unified blog CTA: next_steps shortcode

• New templates/shortcodes/next_steps.html + sass/_next-steps.scss: a calm, docs-box CTA with an optional post-specific context line and two self-select paths (For your team -> /services, For yourself -> /mentorship).
• Replaced the ad-hoc, team-only {% info(icon="crab") %} CTAs across 12 posts so every article routes both audiences consistently.

3. Thinned salesy copy

• memory-safety: removed redundant mid-article CTA boxes and the "Cost of Inaction" insurance pitch; kept the substantive regulatory content + internal links and a single end CTA.
• long-term-rust-maintenance and why-rust: collapsed mixed/duplicate CTA boxes down to one next_steps.

4. Navigation

• Reordered by a left-to-right commitment gradient: Home . Blog . Podcast . Migrate . Workshops . Mentorship . Consulting. Groups the two services adjacently and leads with the high-traffic content; Consulting stays the primary CTA button.

5. Copy fix

• Mentorship FAQ now references the actual pricing tiers (5-session block = 3 months, 10-session block = 6 months) instead of nonexistent "Pack" / "Deep Dive" names.

Validation

• zola build -> 89 pages, 0 orphan.
• /pro redirect alias verified; no stray /pro links remain.

Note for reviewers

The first commit ("Pro turns into Mentorship") also bundles a pre-existing refactor that extracts the inline <nav> from base.html into templates/snippets/nav.html (+ minor nav styling in _base.scss). Happy to split that out if you'd prefer it separate.