[SUPPORT] Hard Delete Operation Fails for Tables with Single Record Key and Partitioning

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Description:
Hard delete operations are failing specifically for Hudi tables that have a single record key with partitioning, while working correctly for other table configurations.

Configurations Tested:
1. Single Record Key, No Partitions - WORKING
2. Single Record Key, With Partitions - NOT WORKING
3. Multiple Record Keys, No Partitions - WORKING
4. Multiple Record Keys, With Partitions - WORKING

Configuration Used in Delete Operation:
```python
write_conf = {
'hoodie.table.name': table_name,
'hoodie.datasource.write.recordkey.field': '_id', # Single record key
'hoodie.datasource.write.precombine.field': precombine_key,
'hoodie.datasource.write.operation': 'delete',
'hoodie.populate.meta.fields': 'true',
'hoodie.cleaner.policy': 'KEEP_LATEST_COMMITS',
'hoodie.cleaner.commits.retained': '1',
'hoodie.metadata.ignore.spurious.deletes': 'false',
'hoodie.bloom.index.prune.by.ranges': 'false',
'hoodie.datasource.write.payload.class': 'org.apache.hudi.common.model.EmptyHoodieRecordPayload'
}

# Partition Configuration
partition_conf = {
'hoodie.datasource.write.partitionpath.field': 'year,month',
'hoodie.datasource.write.hive_style_partitioning': 'true',
'hoodie.table.keygenerator.class': 'org.apache.hudi.keygen.CustomKeyGenerator'
}

A clear and concise description of the problem.

**To Reproduce**

Steps to reproduce the behavior:

1. Create Hudi tables with the following configurations: a. Single record key without partitions b. Single record key with partitions (year, month) c. Multiple record keys without partitions d. Multiple record keys with partitions

2. Insert sample data into all tables

3. Attempt hard delete operation using the following code:
delete_df.write.format("org.apache.hudi") \
.options(**hudi_options) \
.mode("append") \
.save(table_path)

Expected Behavior:
Records should be deleted from all table configurations when performing hard delete operation
Actual Behavior:
Delete operation works for:
Single record key without partitions
Multiple record keys without partitions
Multiple record keys with partitions

Delete operation fails for:
Single record key with partitions
Impact:
This bug affects data deletion operations in partitioned tables with single record keys, which is a common use case in data lakes. It prevents proper data cleanup and management of these tables.

Additional Notes:

The delete operation doesn't throw an error but fails to remove the records
The schema and partition information are correctly maintained in the delete_df
The same configuration works for other table types
CustomKeyGenerator is being used as per table creation configuration
Possible Investigation Areas:
Interaction between CustomKeyGenerator and single record key in partitioned tables
Partition path handling during delete operations
Record key to partition mapping in delete scenarios
Workaround:
Currently, no known workaround has been identified for this specific configuration.

A clear and concise description of what you expected to happen.

**Environment Description**

* Hudi version : 0.12.1

* Spark version : 3.3

* Hive version : 3.1.3

* Hadoop version : 3.3.3

* Storage (HDFS/S3/GCS..) : S3

* Running on Docker? (yes/no) : No

**Additional context**

Add any other context about the problem here.

**Stacktrace**

```Add the stacktrace of the error.```

Start by reproducing the four Hudi table configurations with Spark using the supplied delete options, focusing on the single-record-key partitioned case and CustomKeyGenerator. Compare the partition path and record-key handling with the configurations that succeed; done means hard deletes remove records from the partitioned single-key table without disrupting its schema or partition metadata.

Written by the indexing model from the issue text.