* docs(quickstart): redesign demo-warehouse callout with sticker icons
Replaces the plain warning-style callout with a two-column layout: text
and a pill-shaped CTA on the left, a 2x2 cluster of rotated Postgres,
Metabase, dbt, and Notion sticker tiles on the right. Adds the four
connector SVGs under docs-site/public/icons/ to support it.
* chore(docs-site): refresh auto-generated next-env.d.ts
Bumps font sizes across the in-app React Flow diagram and the README's
SVG so block titles, stage names, body copy, and chip labels are easier
to read. Widens stage cards and updates the SVG layout so every stage
body wraps to two lines, and resizes every badge rect to fit its text
with even 12px padding on both sides (notably the PostgreSQL chip).
Also includes a pre-existing README addition noting that KTX runs with
the user's own LLM keys or a Claude Pro/Max subscription.
Replace the PNG mascot with the refined "C" SVG (light + dark variants)
and enlarge the nav logo from 32px to 56px so it reads at a glance.
Also drop the same SVG pair into assets/ for repo-wide reuse.
