Doku-Hälfte zu 4.7.0: redundant_see_also in tools/CONTRACT.md und wiki-lint, xref-remove-Falle benannt (4.7.1, #49)

Files changed:
- CHANGES.md
- VERSION
- instructions/wiki-lint/SKILL.md
- tools/CONTRACT.md

instructions/wiki-lint/SKILL.md

@@ -26,8 +26,18 @@ never something an agent has to remember.
    unreadable frontmatter, broken wikilinks, dangling frontmatter references, orphan pages,
    catalog drift, missing fields, duplicate titles, filename/title mismatches, broken
    `raw_files:` references, raw files claimed by more than one source page, invalid type paths,
-   schema failures and citation/frontmatter drift. **Do not re-derive any of it by reading
-   pages.**
+   schema failures, citation/frontmatter drift, and edges whose label is missing, not authorised
+   by the source collection, or redundant beside a specific label on the reverse direction.
+   **Do not re-derive any of it by reading pages.**
+
+   The *Redundant see-also* section is the one that looks mechanical and is not - do **not**
+   clear it under step 7. It names a `see-also` edge standing beside a specific label on the
+   reverse direction, and the obvious repair destroys the thing worth keeping: `xref remove`
+   clears the reference in *both* directions (see [tools/CONTRACT.md](../../tools/CONTRACT.md)),
+   so removing the weak edge takes the labelled one with it and the pair ends up saying nothing
+   at all. Either relabel the weak edge to something true with `xref add`, which only ever
+   touches the source page, or leave it and report it at step 9. Clearing a batch of these is a
+   planned corpus sweep with its own run, never a reaction inside a lint.
 
    **To see more of the report, read the file - never run `lint` again.** A second run costs a
    budget slot and re-measures a corpus that has not changed. The file at step 9 overwrites this