[docs] Update DenomOwners information in x/bank if needed

[Unique-Divine]

⚠️ Potential issue | 🟠 Major

Fix DenomOwners description and trailing comma in JSON.

Clarify purpose; remove invalid trailing comma.

-The `DenomOwners` endpoint allows users to query metadata for a single coin denomination.
+The `DenomOwners` endpoint allows users to query all owners (addresses) and balances for a denomination.
@@
   "denomOwners": [
@@
-    }
-  ],
+    }
+  ],

Committable suggestion skipped: line range outside the PR's diff.

🤖 Prompt for AI Agents

In x/bank/README.md around lines 785 to 827, the DenomOwners section currently
misdescribes the endpoint and includes an invalid trailing comma in the example
JSON; change the description to state that DenomOwners returns the list of
account owners and their balances for a given coin denom (not generic "metadata
for a single coin denomination"), and edit the example JSON to remove the
trailing comma after the second denomOwners item and ensure pagination/total
reflect proper formatting (no dangling commas).

Originally posted by @coderabbitai[bot] in #2397 (comment)