Docs: Add NVIDIA GTC 2026 blog skeletons and OpenSpec documentation

[NickJLange]

This PR adds the skeletons for the 11-part NVIDIA GTC 2026 blog series and the associated OpenSpec change documentation.

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Summary by cubic

Adds skeletons for an 11-part NVIDIA GTC 2026 blog series and OpenSpec docs that define the series. Updates latest-post.json to the Vertical AI post.

• New Features

  • Blog series: 11 posts (intro + 10 themed) with consistent frontmatter, <!-- truncate -->, and TODOs referencing mkai/gtc2026.
  • OpenSpec: spec-driven docs under openspec/changes/nvidia-gtc-series/ (.openspec.yaml, design, proposal, spec, tasks) outlining requirements and scope.
  • Content feed: src/generated/latest-post.json now points to the Vertical AI post.

• Bug Fixes

  • Corrected OpenSpec change directory name to nvidia-gtc-series.

^{Written for commit 3fd21cf. Summary will update on new commits. Review in cubic}

[cubic-dev-ai]

1 issue found across 19 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="openspec/changes/nvdia-gtc-series/tasks.md">

<violation number="1" location="openspec/changes/nvdia-gtc-series/tasks.md:1">
P3: The change directory name appears misspelled (`nvdia` vs `nvidia`), which can make this spec harder to find and maintain.</violation>
</file>

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