Contract versions

The current skin contract is version 9: registered component CSS knobs carry every visual decision, sizing included, published one slice per paint family under /r/contract/, indexed by /r/contract/index.json.

A pack written against the current version installs and paints with no migration. Contract versions only matter when installed source and installed skin were written against different ones.

Crossing a version reinstalls core, the affected components or their blocks, and the skin together. Updating one side alone is what leaves knobs declared by nobody.

Version 9 removed the code-block-editor item. It was a second implementation of the code surface with the same anatomy and a parallel --cui-code-block-editor-* knob set, so a skin had to paint the same code panel twice. From version 8 or earlier, remove the old files before reinstalling code:

Then drop the CodeBlockEditor prefix from every part: CodeBlockEditorHeader becomes CodeHeader, CodeBlockEditorContent becomes CodeContent, and so on. CodeBlockEditorTextarea becomes CodeEditable. highlightCodeToTokens moves to highlightToTokens from lib/code-tokens. In a skin, repoint --cui-code-block-editor-* to the matching --cui-code-* knob and any [data-control-family="code-block-editor"] selector to code; the editable textarea is [data-slot="editor"].

variant="command" is gone with no replacement — it set no paint of its own. A one-line command surface is a headerless Code with density="compact" and overflow="wrap".

Version 4 replaced ToolCall with Activity's typed tool variant. From version 3 or earlier, remove both old layouts before reinstalling:

Then replace ToolCall with <Activity kind="tool" name="…"> and its Activity* parts — ActivityDetail, ActivityDetailLabel, ActivityDetailContent — mapping provider status directly to ActivityState. Drop useToolCall; no legacy selectors ship.