README and docs updates

[thejchap]

Context

Remove the branded icon and embedded demo video from the project surfaces.

Changes

• Remove the icon from the README, docs theme and social metadata, and playground chrome.
• Delete the docs and playground logo assets.
• Remove the embedded video from the README and docs landing page.

Test plan

• uv run cargo run -- test --reporter llm
• uv run cargo nextest run --workspace --all-features
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• uv run zensical build --clean
• uvx prek run -a

[Copilot]

Pull request overview

Removes Tryke branding assets (logo/icon) and embedded demo video from the project’s public surfaces (README, docs site, and playground), while refreshing the docs landing page layout to stand on its own without the video/logo.

Changes:

• Removes logo/favicon configuration and OG/Twitter image metadata from the docs theme/config.
• Updates README and docs landing page to remove the embedded demo video; introduces a new homepage hero + feature grid.
• Removes the playground logo chrome (toolbar image + favicon reference).

Reviewed changes

Copilot reviewed 9 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
zensical.toml	Drops theme logo/favicon and the social image extra config.
README.md	Removes the centered icon block and embedded demo video.
playground/src/Editor/Chrome.tsx	Removes the toolbar logo image, keeping only the title link.
playground/index.html	Removes the favicon link referencing the deleted logo asset.
docs/stylesheets/extra.css	Adds styles for the new homepage hero and feature-card grid.
docs/overrides/main.html	Removes OG/Twitter image tags that referenced the logo asset.
docs/overrides/home.html	Adds a dedicated homepage template with a hero section and CTAs.
docs/index.md	Switches to the new homepage template and replaces the video/highlights list with feature cards and refreshed quick-start content.
.markdownlint-cli2.yaml	Allows additional HTML elements used in the docs homepage markup.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.