fix: obfuscate mailto email addresses to prevent scraping (#106)

[designbyalex]

Closes #106.

Summary

• Encode contactEmail / contactCc as base64 at the server→client boundary in components/layout/layout.tsx and decode them in a new <MailtoLink /> client component via useEffect, so addresses never appear in SSR HTML or the hydration payload.
• Remove the plaintext pennywalker@ssw.com.au and +61 2 9953 3000 link entries from the footer per request — the footer's primary CTA mailto button stays.
• Implements the fallback approach from the SSW rule when a contact form isn't feasible: https://www.ssw.com.au/rules/avoid-using-mailto-on-your-website

Why

Issue #106 flagged that mailto: href attributes were exposing plaintext email addresses to scrapers. Acceptance criteria called for the email contact to remain usable while removing the plaintext exposure across all occurrences.

What changed

New

• lib/email-obfuscation.ts — isomorphic base64 encode/decode + buildMailtoHref helper.
• components/ui/mailto-link.tsx — 'use client' component that renders <a href="#contact"> server-side and swaps to a real mailto: URL via useEffect after hydration. Forwards refs so it composes with <Button asChild>.

Modified

• components/layout/layout.tsx — encodes contactEmail / contactCc once and strips the plaintext fields before they reach LayoutProvider.
• components/layout/layout-context.tsx — exposes encodedContactEmail / encodedContactCc via context.
• components/blocks/fbc-pricing.tsx, components/blocks/fbc-certification.tsx, components/blocks/fbc-cta-banner.tsx — swap <a href={mailtoLink}>…</a> for <MailtoLink> (still wrapped by <Button asChild>).
• components/layout/nav/footer.tsx — primary CTA now uses <MailtoLink>; deleted the dead link.href.startsWith('mailto:…') branch and the duplicate contactEmailLink constant.
• components/layout/nav/header.tsx — removed unused mailtoLink dead code.
• content/global/index.json — removed pennywalker@ssw.com.au and +61 2 9953 3000 link entries.

Editors keep entering plaintext into the TinaCMS Global → Contact Email field. Encoding is internal.

Test plan

• pnpm install, pnpm dev, open http://localhost:3000
• View source: confirm zero matches for pennywalker, adamcogan, 9953 3000, and mailto:
• Click each CTA (Apply now / Commit / Submit) on Pricing, Certification, CTA Banner, and Footer — verify the email client opens with correct To, CC, Subject, and Body
• Confirm the footer no longer shows the email or phone-number rows
• DevTools → Network → main document: search payload for pennywalker / adamcogan — zero matches
• In TinaCMS admin (/admin), edit Global → Contact Email, save, verify a CTA opens mailto: with the new address
• pnpm lint clean

🤖 Generated with Claude Code

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