wiki-lint: improve backlink checker to normalize slugs before validation

.claude/commands/wiki-lint.md

@@ -59,10 +59,16 @@ Scan all `[[link]]` references in wiki articles. For each `[[slug]]`, check:
 - If none match → flag as `[BROKEN_LINK]`
 
 ```bash
-grep -rh '\[\[' wiki/ | grep -oP '\[\[\K[^\]]+' | sort -u
+grep -rh '\[\[' wiki/ | grep -o '\[\[[^]]*\]\]' | sed 's/\[\[//;s/\]\]//' | sort -u
 ```
 
-For each unique slug found, verify the file exists.
+For each slug found, normalize before checking:
+1. Strip leading `wiki/` prefix if present → flag as `[BAD_FORMAT]` (seeding agents sometimes write wrong format)
+2. Strip trailing `.md` extension if present → also flag as `[BAD_FORMAT]`
+3. Check existence: `wiki/<slug>.md`, `wiki/clients/<slug>.md`, `wiki/projects/<slug>.md`, `wiki/systems/<slug>.md`, `wiki/patterns/<slug>.md`
+4. If no file found after normalization → flag as `[BROKEN_LINK]`
+
+Note: `[[systems/neptune]]` will always show as broken until neptune is seeded — that's expected.
 
 ---