M4 — Richer dynamic components

[ajianaz]

Goal

Expand the dynamic component vocabulary.

Tasks

• image component (network + asset, with placeholder/error)
• list component — bind an array, repeat a child template per item
• Conditional visibility (visibleWhen expression on a node)
• Dynamic option sources — fetch dropdown options from an endpoint
• icon / avatar components

Acceptance

• New component types registered in bootstrap + documented in docs/DYNAMIC_UI.md.