Add blog on SoB'26 journey: OpenSwap BIP324 encryption

[YoganshSharma]

Adds a blog post covering my Summer of Bitcoin 2026 project: implementing BIP324 encrypted transport for CoinSwap.
Also includes the config update and the blog image.

[adi-shankara]

Thanks for the report! Please fix the _config.yml indentation for the Yogansh profile, remove the extra closing bracket from the post's categories: YAML, and make front-matter author Yogansh Sharma exactly match the author-profile key.

[adi-shankara]

@YoganshSharma Thanks for the update. The YAML/author-key issues are resolved and the current head passes a local Jekyll build. The article still needs a proofreading and accuracy pass:

• Add missing punctuation/spacing around lines 19, 22, 41, 55, 62–68, 72, 78, and 93.
• Fix the unmatched Markdown emphasis at “**tweakable key*”.
• Replace the broken relative link [bip-0324.mediawiki](bip-0324.mediawiki) with the full BIP 324 URL already used earlier in the post.
• Reword the statement that BIP324 gives an “authenticated encryption handshake.” The post later correctly explains that BIP324 is unauthenticated by default; distinguish encrypted/AEAD transport from the external maker authentication your work adds.

Relevant guidance: writing style, technical content standards, and the pre-submission checklist.