Slice 2: Component Registry + metadata pilot (component #26)

[qwerkilo]

Parent

#1 — context2html Framework

What to build

Add YAML front matter to component #26 (components/26-ECharts 交互式图表集.md) as the pilot, then build context2html/registry.py that can parse it.

Component metadata format (YAML front matter in the .md file):

---
id: 26
name: ECharts 交互式图表集
dependencies: [echarts.min.js, echarts-gl.min.js]
compat_types: [report, article, doc, tutorial, note]
degrade_to: "05"
requires_3d: false
---

Registry API:

• ComponentRegistry.list_components(content_type=None) → list of ComponentInfo (id, name, compat_types)
• ComponentRegistry.get_component(id) → Component object (metadata + html + css + js)
• ComponentRegistry.resolve_dependencies(component_ids) → deduplicated list of lib file names

Component fields: id, metadata (ComponentMeta), html, css, js.

ComponentMeta fields: name, dependencies, compat_types, degrade_to, requires_3d.

The existing scripts/extract-component.py continues to work unmodified — the code-block extraction logic stays the same; the front matter is parsed alongside it.

Acceptance criteria

• python -c "from context2html.registry import ComponentRegistry; reg = ComponentRegistry(); c = reg.get_component(26)" returns a Component with correct id, name, and dependencies
• reg.list_components(content_type="doc") includes #26
• reg.resolve_dependencies([26]) returns ["echarts.min.js", "echarts-gl.min.js"]
• Tests use real component file as fixture (not synthetic)
• All 376 existing tests still pass

Blocked by

• Slice 1: Python package scaffolding (prefactor) #2