docs: clarify Raft leader lease timing

[wenxiaojie1]

What is changed, added or deleted? (Required)

Document the startup constraint for raft-store-max-leader-lease: its value must leave one raft-base-tick-interval before the Raft election timeout. This reflects the TiKV configuration validation and helps prevent invalid timing configurations from causing startup failures.

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What is the related PR or file link(s)?

• This PR is translated from:
• Other reference link(s): TiKV Configuration File: The dependencies between parameters should be clearly described #20966, https://github.com/tikv/tikv/blob/master/components/raftstore/src/store/config.rs

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• The changes in this PR were primarily made by an AI agent on behalf of the PR author.

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[gemini-code-assist]

Code Review

This pull request updates the tikv-configuration-file.md documentation to add a constraint for the raft-store-max-leader-lease configuration option. The review feedback suggests rewriting the added sentence in the second person ("you") to align with the repository style guide and removing unnecessary backticks around the numeric literal 1.

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[gemini-code-assist]

According to the repository style guide, we should write in the second person ("you") when addressing users. Additionally, the number 1 in the formula does not need to be in backticks as it is a numeric literal rather than a configuration option or command.

Suggested change

	+ To start TiKV successfully, set this value to no more than `raft-base-tick-interval` * (`raft-election-timeout-ticks` - `1`).
	+ To start TiKV successfully, you must set this value to no more than `raft-base-tick-interval` * (`raft-election-timeout-ticks` - 1).

References

1. Write in second person ("you") when addressing users. ^(link)