v0.41.0 — Composed runes you can ship

Found by WORK-625, the composed character. A {% hint %} an author wrote before the first section was matched by no preamble field and dropped, with no error and no warning. The composed definition works around it with a catch-all body preamble field. SPEC-145 records the finding beside the character worked example.D11 promises against this silent loss but checks the other direction. It requires that every declared field is placed by a slot. Nothing checks that every authored node is matched by a field. So content can still vanish between the author's file and the content model, by another route.This applies to any content model, not just compositions. A tree-owning rune with a narrow preamble loses unmatched content the same way, so the fix belongs in the content-model resolver, not in the composition layer. First measure how many shipped runes drop content today, so the change can be staged as a warning before an error if needed.

SPEC-153 implementation note 4, the project side, and the step that opens composition to users. A project declares runes.dir in refrakt.config.json, following contentDir's shape, with a recommended default of runes (D4). The loader discovers every <rune>.md in it.Decisions:

Composition ships to users in this milestone, and SPEC-153 D9 makes the definition file the user-facing authoring surface. Today the only documentation is a PluginRune note in rune-authoring/authoring-overview.md. Add a page under site/content/extend/rune-authoring/ written from SPEC-145's "template vocabulary, in one place" table. The guide is the spine of that table rather than a summary of it.It covers:

WORK-631 added content-unmatched: validation reports an authored node that no content-model field matches, because the transform drops it. It shipped as a warning because the measurement found that four shipped runes drop real content today, all in the plan plugin. The plan site renders each entity through its rune ({% expand %}), so the loss reaches plan.refrakt.md.Measured over this repo's plan/ directory (907 files), as of WORK-631: