Fix a small bug on DT64->T->T64 conversion

[yariks5s]

Changelog category (leave one):

• Bug Fix (user-visible misbehavior in an official stable release)

Changelog entry (a user-readable short description of the changes that goes into CHANGELOG.md):

Fixes a bug where SELECT CAST(CAST(now(), 'Time'), 'Time64') was producing incorrect result. Closes #88349

Documentation entry for user-facing changes

• Documentation is written (mandatory for new features)

[clickhouse-gh]

Workflow [PR], commit [fecfcbe]

Summary: ❌

job_name	test_name	status	info	comment
Build (amd_compat)		failure
	Cmake configuration	failure	cidb
Stateless tests (amd_binary, ParallelReplicas, s3 storage, parallel)		failure
	02494_query_cache_ignore_output_settings	FAIL	cidb
Integration tests (amd_tsan, 3/6)		failure
	test_backup_restore_s3/test.py::test_backup_to_s3_different_credentials[data_file_name_from_first_file_name-native_multipart]	FAIL	cidb
AST fuzzer (amd_tsan)		failure
	Logical error: 'Unexpected return type from isNotDistinctFrom. Expected UInt8. Got Nothing. Action:	FAIL	cidb
BuzzHouse (amd_debug)		failure
	Logical error: 'Inconsistent AST formatting: the query:	FAIL	cidb
BuzzHouse (arm_asan)		failure
	Received signal 11	FAIL	cidb
BuzzHouse (amd_ubsan)		failure
	/home/ubuntu/actions-runner/_work/ClickHouse/ClickHouse/src/Common/ProfileEvents.cpp:1512:64: runtime error: signed integer overflow: -9085927566061029451 - 9016420377433257301 cannot be represented in type 'Increment' (aka 'long')	FAIL	cidb

[yariks5s]

Provided test requires #90310

[Copilot]

Pull Request Overview

This PR fixes a bug in the conversion chain from DateTime64 to Time to Time64, where intermediate Time values (represented as seconds) were incorrectly treated as day numbers during the final conversion to Time64.

Key Changes:

• Fixed ToTime64Transform::execute(Int32 d, ...) to correctly preserve Time values (seconds) instead of misinterpreting them as day numbers
• Added test cases to verify the fix for the specific conversion path: DateTime64 -> Time -> Time64

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/Functions/FunctionsConversion.h	Fixed ToTime64Transform::execute(Int32, ...) to directly use seconds value instead of incorrectly converting through fromDayNum
tests/queries/0_stateless/03365_time_to_time64_conv_bug.sql	Added test queries for DateTime64->Time->Time64 conversion chain
tests/queries/0_stateless/03365_time_to_time64_conv_bug.reference	Expected results showing correct time preservation through conversion chain

[yariks5s]

Build (amd_compat) - #90492

Stateless tests (amd_binary, ParallelReplicas, s3 storage, parallel) -- flaky

Integration tests (amd_tsan, 3/6) -- flaky

AST Fuzzer and BuzzHouse are not related.