fix: types/type-spec.schema.yaml enforced against real type-spec frontmatter, doc-pull-through.md docs/-page count corrected (closes #105)

Files changed:
- CHANGES.md
- VERSION
- instructions/dev/doc-pull-through.md
- tools/CONTRACT.md
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/tests/test_docs_verify.py
- types/type-spec.md
- types/type-spec.schema.yaml

tools/chemenu/tests/test_docs_verify.py

@@ -1,8 +1,9 @@
 import pytest
 import typer
 
-from chemenu import config
+from chemenu import config, type_resolver
 from chemenu.commands import dist_cmd, docs_verify
+from chemenu.type_resolver import TypeResolver
 
 
 def test_every_registered_command_is_documented():
@@ -289,6 +290,51 @@ def test_an_absent_listed_doc_is_skipped_not_reported(tmp_path, monkeypatch):
     assert docs_verify.check_readmes_have_no_command_table() == []
 
 
+def test_this_repos_type_specs_validate_against_their_own_schema():
+    """Regression guard for Gitea #105: types/type-spec.schema.yaml declared
+    `additionalProperties: false` while real type-specs already carried
+    `root:` and `capture_fields:`, and nothing ever validated a type-spec's
+    own frontmatter against it - so the mismatch shipped silently."""
+    assert docs_verify.check_type_spec_frontmatter() == []
+
+
+def test_an_unknown_type_spec_field_is_reported(tmp_path, monkeypatch):
+    """Once the schema is enforced, a type-spec frontmatter field its own
+    schema does not know about must fail loudly rather than validating
+    silently - the other direction of the #105 regression guard above."""
+    types_dir = tmp_path / "types"
+    types_dir.mkdir()
+    (types_dir / "type-spec.md").write_text(
+        "---\n"
+        "type: types/type-spec.md\n"
+        "name: type-spec\n"
+        "description: Authoring and validation contract for type specs\n"
+        "schema: types/type-spec.schema.yaml\n"
+        "---\n",
+        encoding="utf-8",
+    )
+    (types_dir / "type-spec.schema.yaml").write_text(
+        (config.ROOT / "types" / "type-spec.schema.yaml").read_text(encoding="utf-8"),
+        encoding="utf-8",
+    )
+    (types_dir / "widget.md").write_text(
+        "---\n"
+        "type: types/type-spec.md\n"
+        "name: widget\n"
+        "description: A type-spec with a field its own schema does not know\n"
+        "schema: null\n"
+        "not_a_real_field: true\n"
+        "---\n",
+        encoding="utf-8",
+    )
+    monkeypatch.setattr(config, "ROOT", tmp_path)
+    monkeypatch.setattr(config, "TYPES_DIR", types_dir)
+    monkeypatch.setattr(type_resolver, "resolver", TypeResolver(repo_root=tmp_path))
+
+    issues = docs_verify.check_type_spec_frontmatter()
+    assert any("widget.md" in issue and "not_a_real_field" in issue for issue in issues)
+
+
 def test_legacy_type_blocks_are_absent():
     assert docs_verify.check_legacy_type_blocks() == []