admin: document query params for /v1/cloud_storage/cache/trim

[nvartolomei]

Backports Required

• none - not a bug fix
• none - this is a backport
• none - issue does not exist in previous branches
• none - papercut/not impactful enough to backport
• v24.3.x
• v24.2.x
• v24.1.x

Release Notes

• none

[vbotbuildovich]

Retry command for Build#60014

please wait until all jobs are finished before running the slash command

/ci-repeat 1
tests/rptest/tests/e2e_shadow_indexing_test.py::ShadowIndexingWhileBusyTest.test_create_or_delete_topics_while_busy@{"cloud_storage_type":2,"short_retention":true}

[vbotbuildovich]

CI test results

test results on build#60014

test_id	test_kind	job_url	test_status	passed
rptest.tests.datalake.partition_movement_test.PartitionMovementTest.test_cross_core_movements.cloud_storage_type=CloudStorageType.S3	ducktape	https://buildkite.com/redpanda/redpanda/builds/60014#0193e567-c231-45a9-be62-a2adc523e4ca	FLAKY	3/6
rptest.tests.e2e_shadow_indexing_test.ShadowIndexingWhileBusyTest.test_create_or_delete_topics_while_busy.short_retention=True.cloud_storage_type=CloudStorageType.ABS	ducktape	https://buildkite.com/redpanda/redpanda/builds/60014#0193e582-a493-42d4-8582-162a623c76d1	FAIL	0/6
rptest.transactions.stream_verifier_test.StreamVerifierTest.test_simple_produce_consume_txn_with_add_node	ducktape	https://buildkite.com/redpanda/redpanda/builds/60014#0193e567-c235-4155-a5a2-d874434c5c37	FLAKY	5/6