Use API-agnostic language in partition key immutability callout

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Co-authored-by: seesharprun <5067401+seesharprun@users.noreply.github.com>

Author: Copilot

articles/cosmos-db/partitioning.md

@@ -102,7 +102,7 @@ For **all** containers, the partition key should:
 * Be a property that has a value, which doesn't change. If a property is your partition key, you can't update that property's value.
 
   > [!IMPORTANT]
-  > **Partition key values are immutable.** Once an item is created, its partition key value cannot be changed in place. A ReplaceItem operation requires the partition key to match the existing item — you cannot use it to move an item between partitions. To "move" an item, you must create a new item with the new partition key value and delete the original item. These two operations cannot be performed atomically across different logical partitions.
+  > **Partition key values are immutable.** Once an item is created, its partition key value cannot be changed in place. An item replacement operation requires the partition key to match the existing item — you cannot use it to move an item between partitions. To "move" an item, you must create a new item with the new partition key value and delete the original item. These two operations cannot be performed atomically across different logical partitions.
 
 * Contain only `String` values—or convert numbers into a `String` if they might exceed the boundaries of double precision numbers according to [Institute of Electrical and Electronics Engineers (IEEE) 754 binary64](https://www.rfc-editor.org/rfc/rfc8259#ref-IEEE754). The [Json specification](https://www.rfc-editor.org/rfc/rfc8259#section-6) explains why using numbers outside this boundary is a bad practice due to interoperability problems. These concerns are especially relevant for the partition key column because it's immutable and requires data migration to change later.