Document server-side name cap and hidden-rune rejection

OPERATIONS.txt

@@ -172,7 +172,12 @@ response records high, medium or low confidence. Imports never auto-apply a
 low-confidence category: the row keeps the kind-specific unclassified
 category with merchant and confidence recorded. Analyse previews show the
 low-confidence suggestion unselected for review. Transactions exposes a
-Needs review filter for low-confidence or fallback rows.
+Needs review filter for low-confidence or fallback rows. A model-proposed
+merchant name is dropped (the row keeps its validated category and tags)
+when it is identifier-shaped, longer than 100 characters, or contains
+control or format code points such as bidirectional overrides and
+zero-width characters, which could visually spoof the review UI; proposed
+taxonomy names are rejected under the same hidden-rune rule.
 
 Categories and tags have editable hints. Categories -> Propose taxonomy sends
 up to 300 grouped, redacted transaction samples, then shows proposed
@@ -701,7 +706,9 @@ The grammar is version-one strict: extension/split fields are not accepted yet.
 Future format extensions require an explicit parser migration.
 
 Stable category IDs survive renaming and moving; assigned categories must remain
-leaves. Built-in roots and fallback leaves are protected. Move assigned records
+leaves. Registry display names (category, tag, merchant, instrument) are
+capped at 200 characters server-side, matching every UI form. Built-in roots
+and fallback leaves are protected. Move assigned records
 to another leaf before adding children to their former category. Category
 merges migrate referenced transactions/defaults; tag merges deduplicate links;
 tag deletion removes all affected links after UI confirmation. Merchant merging