Pagination discrepancy for MemorySessionManager ---> search_long_term_memories and list_long_term_memory_records

**Describe the bug**
MemorySessionManager has 2 memory listing methods named search_long_term_memories and list_long_term_memory_records

as per boto3 docs both the methods should support pagination with nextToken

i can see list_long_term_memory_records has some pagination inside it and fetches all the records in loop where as search_long_term_memories doesnt have one

both methods pagination logic should be similar as per boto3 actual methods? if yes, search_long_term_memories also needs same looping logic and fetching all records

Also as list_long_term_memory_records brings up all the records in a loop and then do the slicing as per max_results,

- what if the records are huge in number?
- Is sequential pagination will be available in future? as even if i increase max_results value to a bigger number, i will get the values from the beginning till max_result always

**Screenshots**

boto3 links:
https://docs.aws.amazon.com/boto3/latest/reference/services/bedrock-agentcore/client/retrieve_memory_records.html
https://docs.aws.amazon.com/boto3/latest/reference/services/bedrock-agentcore/client/list_memory_records.html

Start at MemorySessionManager.search_long_term_memories and list_long_term_memory_records, then compare their nextToken handling with the linked boto3 retrieve_memory_records and list_memory_records documentation. Confirm the intended pagination and max_results behavior; done means both methods have consistent, documented results without ambiguous retrieval semantics.

Written by the indexing model from the issue text.