stack: TOC-Pflicht fuer Referenzdateien ueber 100 Zeilen (docs toc); session-setup.md/gates.md nennen die tatsaechliche Budget-Ausnahmeliste (schliesst #73, #76)

Files changed:
- AGENTS.md
- CHANGES.md
- VERSION
- instructions/CONTRACT.md
- instructions/capture-session.md
- instructions/claude-code-model-selection.md
- instructions/dev/issue-tracking.md
- instructions/dev/testing-conventions.md
- instructions/dev/version-parts.md
- instructions/evolve-subtypes.md
- instructions/gates.md
- instructions/german-terminology.md
- instructions/ingest-large-tree.md
- instructions/kb-profiles.md
- instructions/link-taxonomy.md
- instructions/mcp-read-server.md
- instructions/migrate-corpus.md
- instructions/migrations/3.0.0-authoring-conventions.md
- instructions/migrations/4.0.0-link-taxonomy.md
- instructions/private-instance.md
- instructions/session-setup.md
- instructions/setup-instance.md
- kb/CONTRACT.md
- kb/CONVENTIONS.md
- kb/concepts/COLLECTION.md
- raw/CONTRACT.md
- tools/CONTRACT.md
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/commands/instructions_cmd.py
- tools/chemenu/tests/test_docs_verify.py
- tools/chemenu/tests/test_instructions_cmd.py
- tools/chemenu/tests/test_toc.py
- tools/chemenu/toc.py
- types/type-spec.md

instructions/migrate-corpus.md

@@ -16,6 +16,16 @@ defects this way - a dropped citation that silently unsourced a claim, a dropped
 invented one, and a translated H1 - and three of the four had unchanged link *sets* and only
 changed counts.
 
+<!-- wikitool:toc -->
+## Contents
+
+- [When to run](#when-to-run)
+- [Steps](#steps)
+- [Decision points](#decision-points)
+- [Writing the migration document](#writing-the-migration-document)
+- [Scope](#scope)
+<!-- /wikitool:toc -->
+
 ## When to run
 
 A change that would otherwise be applied to more than a handful of pages by hand, or any change