chore(blog): label Chapel code fences

[Jesssullivan]

Summary

• Bump Shiki to 4.2.0.
• Add the chpl alias around the existing vendored Chapel grammar.
• Relabel Chapel source blocks in the Chapel/Dhall post from text to chapel.

Paired tinyland.dev PR: https://github.com/tinyland-inc/tinyland.dev/pull/603.

Validation

• node --input-type=module ... spoke Chapel/chpl Shiki smoke: passed.
• node --input-type=module -e "await import('./svelte.config.js')": passed.
• Checked from the paired tinyland.dev branch: managed/spoke Chapel/Dhall body drift clears when using this branch as --source-dir; only three unrelated missing managed posts remain.

[github-actions]

📝 Blog Post Review

Found 1 blog post(s) in this PR:

Post	Status	Date	Published	Tags	Linear
Host Characterization with Chapel, Fancy Testing & Dhall	✏️ Modified	2026-04-25	✅ Published	Chapel, Nix, Dhall, NUMA, hardware, reproducibility, RT, PBT	none

Schema Validation

✅ All posts pass schema validation.

Hyperlink Suggestions

• Dhall → Dhall (line 243)
• Nix → Nix (line 243)

Slash Commands

Command	Description
/schedule 2026-03-15	Schedule auto-merge for a date
/publish	Set all posts to published: true
/draft	Set all posts back to draft
/retitle "New Title"	Change a post's title
/review	Re-run AI prose review
/suggest-links	Find unlinked keywords