Backport #99084 to 26.1: Try not to re-caclculate indexes in requestReadingInOrder

[robot-ch-test-poll2]

Original pull-request #99084
Cherry-pick pull-request #99186

This pull-request is a last step of an automated backporting.
Treat it as a standard pull-request: look at the checks and resolve conflicts.
Merge it only if you intend to backport changes to the target branch, otherwise just close it.

The PR source

The PR is created in the CI job

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Note

Medium Risk
Touches MergeTree read planning for the read-in-order optimization; while the change is small, incorrect read_type propagation could affect ordering/aggregation behavior in some query plans.

Overview
Avoids re-running selectRangesToRead() when ReadFromMergeTree::requestReadingInOrder() enables the in-order optimization. Instead, if an existing analyzed_result_ptr is present (and not reading from a projection), it now just updates analyzed_result_ptr->read_type based on the requested sort direction (InOrder vs InReverseOrder).

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[clickhouse-gh]

Workflow [BackportPR], commit [e914a90]

Summary: ❌

job_name	test_name	status	info	comment
Stress test (amd_tsan)		failure
	Logical error: Block structure mismatch in A stream: different number of columns: (STID: 0993-2da1)	FAIL	cidb