Decouple TemplateFunc from templ.Component by introducing a generic
HTMLComponent interface that both templ and pongo2 satisfy via Go
structural typing. Add a complete pongo2 rendering engine in
templates/pongo/ with page templates, block templates (with BlockContext
injection and icon processing), template overrides, and email wrappers.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Initialize git.dev.alexdunmow.com/ninja/core with Go 1.26 module,
package directory structure, and README.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>