feat: a subtype gets its own page skeleton from types/<type>.<value>.md (#117)

Files changed:
- AGENTS.md
- CHANGES.md
- README.md
- VERSION
- docs/ownership-and-templates.md
- instructions/evolve-subtypes.md
- instructions/setup-instance.md
- instructions/subtype-templates.md
- instructions/upgrade-instance.md
- tools/CONTRACT.md
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/commands/new_page.py
- tools/chemenu/tests/test_dist_cmd.py
- tools/chemenu/tests/test_docs_verify.py
- tools/chemenu/tests/test_new_page.py
- tools/chemenu/tests/test_toc.py
- tools/chemenu/tests/test_type_resolver.py
- tools/chemenu/toc.py
- tools/chemenu/type_resolver.py
- types/concept.decision.md
- types/entity.guidance.md
- types/entity.md
- types/entity.person.md
- types/type-spec.md

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SnAJ7Z3CpVD3PRbN73QtU2

instructions/subtype-templates.md

@@ -0,0 +1,100 @@
+---
+type: types/instruction.md
+name: subtype-templates
+description: Interview the corpus and the user for page skeletons per subtype - find subtypes whose pages systematically depart from their type's template, propose a types/<type>.<value>.md for each, and write the ones the user accepts.
+manual: true
+---
+# Find the subtypes that need a page skeleton of their own
+
+A page type carries one `## Template` block for every value of its subtype field, and for most
+values that is enough. Where a subtype needs a different page shape - a person is not described by
+a version and a repository, a decision wants its context, alternatives and consequences - authors
+rebuild every scaffolded page by hand, and the corpus shows it. A **subtype template**,
+`types/<type>.<value>.md`, gives that subtype its own skeleton: `wikitool new` takes it instead of
+the block whenever the page's subtype field holds `<value>`. The file's shape and the checks on it
+are [types/type-spec.md](../types/type-spec.md) § "Anatomy of a type".
+
+This instruction is the interview that decides which subtypes get one. It reads the pages first
+and proposes from them, because a template written ahead of the material is a guess every later
+page is scaffolded into.
+
+## When to run
+
+- The user asks for it, by name or by describing the symptom: pages of one kind keep being
+  rebuilt after `wikitool new`.
+- After [evolve-subtypes.md](evolve-subtypes.md) added a value and its pages have accumulated.
+- After an upgrade delivered a subtype template as `.template` beside a type already adopted, and
+  the user wants to know whether to take it.
+
+Not for changing the `## Template` block every subtype shares - that is an edit to the type-spec
+itself. Not for adding a subtype value - that is [evolve-subtypes.md](evolve-subtypes.md).
+
+## Steps
+
+1. **List what there is to examine.** Every type-spec with a `subtype_field:`, every value its
+   schema allows, and which skeleton each value scaffolds today:
+
+   ```bash
+   tools/wikitool types list
+   tools/wikitool types describe <type>
+   ls types/
+   ```
+
+   A value scaffolds from `types/<type>.<value>.md` if that file exists, otherwise from the
+   type-spec's `## Template` block.
+
+2. **Hold each value's pages against the skeleton they were scaffolded from.** Find them and read
+   their `##` headings:
+
+   ```bash
+   tools/wikitool search --field <subtype_field>=<value>
+   ```
+
+   What counts is a departure several pages share: the same template section emptied or deleted,
+   the same section added under the same or an equivalent name, the same section replaced by
+   another. One page's own extra section is that page's business.
+
+3. **Apply the admission threshold of [evolve-subtypes.md](evolve-subtypes.md): at least three
+   pages of one subtype departing the same way.** A template is admitted after the material has
+   shown its shape, never in expectation of it. A smaller count is only ever an explicit exception
+   the user names, never a reason to lower the threshold.
+
+4. **Offer a shipped template as the starting point where one is lying ready.** A
+   `types/<type>.<value>.md.template` that was never adopted is the stack's proposal for that
+   subtype. Compare it with what the pages actually do, and propose it unchanged, adapted, or not
+   at all.
+
+5. **Put each candidate to the user, one at a time:** which pages, what they share, and a draft
+   of the template in the KB language (`kb/CONVENTIONS.md` `language:`) - the same variables and
+   filters the `## Template` block uses ([types/type-spec.md](../types/type-spec.md) § "Template
+   variables"), no frontmatter, no fence, no tool-owned section. The user decides per candidate:
+   accept, change, or reject.
+
+6. **Write each accepted template, then check it:**
+
+   ```bash
+   tools/wikitool dist adopt types/<type>.<value>.md.template   # only where step 4 took the shipped one unchanged
+   tools/wikitool docs verify
+   ```
+
+   Otherwise write `types/<type>.<value>.md` directly. `docs verify` refuses a file whose type has
+   no `subtype_field:`, whose value the schema does not allow, or which carries frontmatter.
+
+7. **Leave the existing pages as they are.** A template acts only on the next `wikitool new`;
+   reshaping existing pages to match it is ordinary page editing, decided per page, and not part
+   of this procedure.
+
+## Decision points
+
+- **The departures differ from page to page?** Then no template is warranted: a skeleton that
+  fits none of the pages well is not better than the one they already rebuild.
+- **All subtypes of a type depart the same way?** The `## Template` block itself is wrong, and
+  editing it is the fix - not one subtype template per value.
+- **The value is `guidance`?** It cannot have a template: `types/<type>.guidance.md` is always the
+  type's guidance file. Rename the value instead, through [evolve-subtypes.md](evolve-subtypes.md).
+
+## Scope
+
+Covers every page type that declares `subtype_field:` - in the shipped specs `entity`, `concept`,
+`source` and `project`. A type without one, such as `comparison`, has a single skeleton by
+construction. Does not move, rename or rewrite a page.