Sync Blog.md with post-hackathon training section, Haiku 4.5 n=68 baseline, and corrected references

Sync to local main (commit 1e292cf): post-hackathon blog updates

Add external reference links throughout Viveka blog

Improve blog copy with small fixes

Polish Viveka blog with references and minor fixes

Add research-context references to Viveka blog

- Correct scenario count in Section 2 to 68 across four tiers

docs(blog): expand Viveka overview and training insights

docs(blog): add design-principle framing and frontier baselines

docs(blog): polish prose, add mentor credit, and tighten section voice

docs(blog): refactor Blog.md and add deeper engineering insights

docs: add judge TL;DR table at top of README and Blog

chore(post-eval polish): blog architecture section + Gradio root mount

feat(submission): trained Llama-3B sealed eval + leaderboard PNG + Gradio fix

feat(submission): HF Space deployed + Blog.md + final shims + URLs wired