feat: Prosa ist kein Identifier - Link-Taxonomie als Enum, generierte Regionen mit Markern (4.0.0)

Files changed:
- .gitea/workflows/ci.yml
- AGENTS.md
- CHANGES.md
- VERSION
- instructions/CONTRACT.md
- instructions/link-taxonomy.md
- instructions/migrations/4.0.0-link-taxonomy.md
- instructions/setup-instance.md
- kb/CONTRACT.md
- kb/CONVENTIONS.md
- kb/CONVENTIONS.md.template
- kb/comparisons/COLLECTION.md
- kb/concepts/COLLECTION.md
- kb/entities/COLLECTION.md
- kb/sources/COLLECTION.md
- tools/CONTRACT.md
- tools/README.md
- tools/chemenu/blocks.py
- tools/chemenu/cli.py
- tools/chemenu/commands/cite_cmd.py
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/commands/doctor.py
- tools/chemenu/commands/links_cmd.py
- tools/chemenu/commands/migrate_cmd.py
- tools/chemenu/commands/new_page.py
- tools/chemenu/commands/page_ops.py
- tools/chemenu/commands/run_budget.py
- tools/chemenu/commands/xref.py
- tools/chemenu/conventions.py
- tools/chemenu/corpus_diff.py
- tools/chemenu/frontmatter_io.py
- tools/chemenu/kb_collections.py
- tools/chemenu/kb_state.py
- tools/chemenu/links.py
- tools/chemenu/lint_core.py
- tools/chemenu/provenance.py
- tools/chemenu/sections.py
- tools/chemenu/tests/conftest.py
- tools/chemenu/tests/test_blocks.py
- tools/chemenu/tests/test_cite_cmd.py
- tools/chemenu/tests/test_conventions.py
- tools/chemenu/tests/test_dist_cmd.py
- tools/chemenu/tests/test_doctor.py
- tools/chemenu/tests/test_migrate_cmd.py
- tools/chemenu/tests/test_new_page.py
- tools/chemenu/tests/test_pipeline_l0.py
- tools/chemenu/tests/test_types_cmd.py
- tools/chemenu/tests/test_xref.py
- types/concept.schema.yaml
- types/entity.md
- types/entity.schema.yaml
- types/instruction.schema.yaml
- types/type-spec.md
- work/link-taxonomy-migration/README.md
- work/link-taxonomy-migration/plan.md

tools/chemenu/tests/test_pipeline_l0.py

@@ -41,7 +41,11 @@ def empty_kb(tmp_path, monkeypatch):
     for collection in COLLECTIONS:
         (kb / collection).mkdir(parents=True)
         (kb / collection / "COLLECTION.md").write_text(
-            f"# kb/{collection}/ - Collection Contract\n", encoding="utf-8"
+            f"---\nprofile: {collection}\n"
+            f"required_by_stack: {'true' if collection == 'sources' else 'false'}\n"
+            "outbound:\n  any: [implements, uses, see-also]\n---\n\n"
+            f"# kb/{collection}/ - Collection Contract\n",
+            encoding="utf-8",
         )
     raw = tmp_path / "raw"
     raw.mkdir()
@@ -76,7 +80,8 @@ def build_wiki(kb):
             "--set", "summary=A concept created by the pipeline test"])
     for page in kb.rglob("Pipeline *.md"):
         finish_page(page)
-    invoke(["xref", "add", "--a", "Pipeline Host", "--b", "Pipeline Concept"])
+    invoke(["xref", "add", "--a", "Pipeline Host", "--b", "Pipeline Concept",
+            "--rel", "implements"])
     invoke(["index", "rebuild"])
 
 
@@ -101,12 +106,23 @@ def test_a_wiki_built_by_the_tools_lints_clean(empty_kb):
     assert not has_hard_errors(report), f"hard errors after a clean build: {found}"
 
 
-def test_the_pages_reach_each_other(empty_kb):
-    """`xref add` is what makes two pages findable from one another; if it and
-    the link checker disagreed, the lint above would report a broken link."""
+def test_an_edge_points_one_way_and_the_far_end_stops_being_an_orphan(empty_kb):
+    """`xref add` declares one direction, and that is what the orphan check now
+    measures: reachability.
+
+    It used to assert that *neither* page was an orphan, which only held because
+    `xref add` wrote a mirror edge on the target. With authored directional
+    edges the source of the only edge in a two-page wiki genuinely has nothing
+    pointing at it - so the check reporting it is the check working, not a
+    regression. A real corpus answers this by having entry points that other
+    pages point at."""
     build_wiki(empty_kb)
 
-    assert run_lint(empty_kb)["orphan_pages"] == []
+    report = run_lint(empty_kb)
+    assert "Pipeline Concept" not in report["orphan_pages"]
+    assert report["orphan_pages"] == ["Pipeline Host"]
+    assert report["broken_links"] == []
+    assert report["dangling_frontmatter_refs"] == []
 
 
 def test_the_catalog_covers_what_was_created(empty_kb):