Hidden "How mods work" demo plugin draws an animated Clawd panel over question cards

What

A new built-in plugin, cc-plugin-mods-guide, is registered next to plugin-authoring. Its description reads: "How mods work: asked how hot reloading works, the question card gets a small panel over it with Clawd cooking, gone once the card is answered".

• It uses the ui.render hook (a way for a plugin to change how part of the screen is drawn) on the AskUserQuestion card, the card Claude uses to ask you a question.
• When the question has a multi-line body, it adds a bold "How mods work" header and an animated pixel-art panel of Clawd stirring a pot above the card, using assets such as CLAWD_COOKING_SVG, FLAMES and BUBBLES.
• In the terminal it repaints the picture with ui.blit on a clock.every timer; elsewhere it uses an SVG image.
• It draws nothing when NO_COLOR is set, FORCE_COLOR=0, TERM=dumb, or the window is too small, and it stays still when prefersReducedMotion is set.
• It is available only when tengu_linen_acorn is on (code fallback false, isOnByDefault false) and another check, bh(), is false. It is not registered when CLAUDE_CODE_ENTRYPOINT is local-agent. Nothing has been read about this gate, so whether it is active is unknown.

The AskUserQuestion tool description itself is unchanged, per a prompt capture taken under this release.

Why

It is a working example of what plugins can do with the mods system: drawing over parts of the screen, animating on a timer and reading environment settings, while respecting color and motion preferences.