releases: add release notes for v8.4.0

[Oreoxmt]

First-time contributors' checklist

• I've signed Contributor License Agreement that's required for repo owners to accept my contribution.

What is changed, added or deleted? (Required)

releases: add release notes for v8.4.0

Which TiDB version(s) do your changes apply to? (Required)

Tips for choosing the affected version(s):

By default, CHOOSE MASTER ONLY so your changes will be applied to the next TiDB major or minor releases. If your PR involves a product feature behavior change or a compatibility change, CHOOSE THE AFFECTED RELEASE BRANCH(ES) AND MASTER.

For details, see tips for choosing the affected versions (in Chinese).

• master (the latest development version)
• v8.4 (TiDB 8.4 versions)
• v8.3 (TiDB 8.3 versions)
• v8.2 (TiDB 8.2 versions)
• v8.1 (TiDB 8.1 versions)
• v7.5 (TiDB 7.5 versions)
• v7.1 (TiDB 7.1 versions)
• v6.5 (TiDB 6.5 versions)
• v6.1 (TiDB 6.1 versions)
• v5.4 (TiDB 5.4 versions)
• v5.3 (TiDB 5.3 versions))

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

• This PR is translated from:
• Other reference link(s):

Do your changes match any of the following descriptions?

• Delete files
• Change aliases
• Need modification after applied to another branch
• Might cause conflicts after applied to another branch

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please ask for approval from oreoxmt, ensuring that each of them provides their approval before proceeding. For more information see the Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[JaySon-Huang]

Suggested change

	- note [#issue](https://github.com/pingcap/tiflash/issues/${issue-id}) @[贡献者 GitHub ID](https://github.com/${github-id})
	- 修复当表里含 Bit 类型列并且带有表示非法字符的默认值时 TiFlash 无法解析表 schema 的问题 [#9461](https://github.com/pingcap/tiflash/issues/9461) @[Lloyd-Pottiger](https://github.com/Lloyd-Pottiger)
	- 修复当多个 Region 在并发进行副本同步时，可能错误地触发 Region overlap 检查失败引起的 panic 问题 [#9329](https://github.com/pingcap/tiflash/issues/9329) @[CalvinNeo](https://github.com/CalvinNeo)

[JaySon-Huang]

Suggested change

	- (dup): release-6.5.11.md > 改进提升> TiFlash - 优化 `LENGTH()` 和 `ASCII()` 函数执行效率 [#9344](https://github.com/pingcap/tiflash/issues/9344) @[xzhangxian1008](https://github.com/xzhangxian1008)
	- (dup): release-6.5.11.md > 改进提升> TiFlash - 优化 `LENGTH()` 和 `ASCII()` 函数执行效率 [#9344](https://github.com/pingcap/tiflash/issues/9344) @[xzhangxian1008](https://github.com/xzhangxian1008)
	- 减少处理存算分离请求创建的线程数 [#9334](https://github.com/pingcap/tiflash/issues/9334) @[JinheLin](https://github.com/JinheLin)

[JaySon-Huang]

Suggested change

	| TiFlash | [`storage.format_version`](/tiflash/tiflash-configuration.md) | 修改 | 默认值从 `5` 修改为 `7`，该格式可以支持向量索引的构建与存储。 |

[wuhuizuo]

/retest

[ti-chi-bot]

@Oreoxmt: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-verify	721e5fe	link	true	/test pull-verify

Full PR test history. Your PR dashboard.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.

[time-and-fate]

Suggested change

	- 自动统计信息收集根据节点规模和硬件规格自动确定执行和扫描的并发度 [#53460](https://github.com/pingcap/tidb/issues/53460) @[hawkingrei](https://github.com/hawkingrei) **tw@Oreoxmt** <!--1739-->
	- 自动统计信息收集根据节点规模和硬件规格自动确定执行和扫描的并发度 [#53460](https://github.com/pingcap/tidb/issues/53460) @[hawkingrei](https://github.com/hawkingrei) **tw@Oreoxmt** <!--1739-->
	- 优化一处内部函数逻辑，提升查询列数特别多的表时的性能 [#52112](https://github.com/pingcap/tidb/issues/52112) @[Rustin170506](https://github.com/Rustin170506)
	- 默认开启 `tidb_enable_inl_join_inner_multi_pattern`，扩展 TiDB Index Join 的能力 [#47233](https://github.com/pingcap/tidb/issues/47233) @[winoros](https://github.com/winoros)
	- 支持将形如 `a = 1 AND (a > 1 OR (a = 1 AND b = 2))` 的过滤条件简化为 `a = 1 AND b = 2` [#56005](https://github.com/pingcap/tidb/issues/56005) @[ghazalfamilyusa](https://github.com/ghazalfamilyusa)
	- 在部分选中不优执行计划风险较高的场景中，提高代价模型中 Table Scan 的代价，使得优化器更倾向于使用索引 [#56012](https://github.com/pingcap/tidb/issues/56012) @[terry1purcell](https://github.com/terry1purcell)

[time-and-fate]

Suggested change

	- note [#issue](https://github.com/pingcap/tidb/issues/${issue-id}) @[贡献者 GitHub ID](https://github.com/${github-id})
	- note [#issue](https://github.com/pingcap/tidb/issues/${issue-id}) @[贡献者 GitHub ID](https://github.com/${github-id})
	- 修复一张表索引中包含生成列时，`ANALYZE` 这张表可能报错 “Unknown column 'column_name' in 'expression'” 的问题 [#55438](https://github.com/pingcap/tidb/issues/55438) @[hawkingrei](https://github.com/hawkingrei)
	- 将 `analyze-partition-concurrency-quota` 配置文件参数标记为废弃 [#55043](https://github.com/pingcap/tidb/issues/55043) @[Rustin170506](https://github.com/Rustin170506)
	- 修复执行一条包含关联子查询和 CTE 的查询时，TiDB 可能 hang 住或返回错误结果的问题 [#55551](https://github.com/pingcap/tidb/issues/55551) @[guo-shaoge](https://github.com/guo-shaoge)
	- 修复禁用 `lite-init-stats` 可能导致统计信息同步加载失败的问题 [#54532](https://github.com/pingcap/tidb/issues/54532) @[hawkingrei](https://github.com/hawkingrei)
	- 修复当 `UPDATE` 或 `DELETE` 语句包含 Recursive CTE 时，语句可能报错或不生效的问题 [#55666](https://github.com/pingcap/tidb/issues/55666) @[time-and-fate](https://github.com/time-and-fate)
	- 修复当一条 SQL Binding 涉及窗口函数时，有一定概率不生效的问题 [#55981](https://github.com/pingcap/tidb/issues/55981) @[winoros](https://github.com/winoros)
	- 修复统计信息初始化时，使用非二进制排序规则的字符串类型列的统计信息可能无法正常加载的问题 [#55684](https://github.com/pingcap/tidb/issues/55684) @[winoros](https://github.com/winoros)
	- 修复查询条件为 `column IS NULL` 访问唯一索引的时候，优化器将行数错误地估算为 1 的问题 [#56116](https://github.com/pingcap/tidb/issues/56116) @[hawkingrei](https://github.com/hawkingrei)
	- 修复了当查询包含形如 `(... AND ...) OR (... AND ...) ...` 的过滤条件时，优化器没有使用最优的多列统计信息进行行数估算的问题。 [#54323](https://github.com/pingcap/tidb/issues/54323) @[time-and-fate](https://github.com/time-and-fate)
	- 修复当一个查询有 Index Merge 执行计划可用时，`read_from_storage` hint 可能不生效的问题 [#56217](https://github.com/pingcap/tidb/issues/56217) @[AilinKid](https://github.com/AilinKid)