i18n(ja): translate residual English availability zone left in JA prose

[yahonda]

What is changed, added or deleted? (Required)

3 files had the raw English words "availability zone(s)" left untranslated directly in otherwise-translated Japanese sentences, instead of アベイラビリティゾーン matching the rest of each file's own prose:

• tidb-cloud/setup-aws-msk-provisioned-private-link-service.md (6 sites)
• tidb-cloud/architecture-concepts.md (2 sites)
• tidb-cloud/premium/connect-to-premium-via-aws-private-endpoint.md (4 sites)

Bold UI-field labels matching literal console field names (e.g. **Availability Zone**: \us-west-2a``) are intentionally kept in English elsewhere per the established convention and are unaffected by this change.

Note: this corpus also has a separate, larger 3-way notation split for the "availability zone" concept itself (可用性ゾーン / アベイラビリティゾーン / アベイラビリティーゾーン, ~129 occurrences across 40+ files) — out of scope here since it's a term-unification decision, not a clear mistranslation; will be scoped separately.

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

• i18n-ja-release-8.5 (TiDB Japanese documentation for TiDB 8.5 versions)

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

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

AI agent involvement

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

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 assign tangenta for approval. For more information see the Code Review Process.
Please ensure that each of them provides their approval before proceeding.

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

Details

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

[coderabbitai]

📝 Walkthrough

Walkthrough

Changes

AWS関連ドキュメント更新

Layer / File(s)	Summary
アベイラビリティゾーン表記の統一 tidb-cloud/architecture-concepts.md, tidb-cloud/premium/connect-to-premium-via-aws-private-endpoint.md	AWS関連の説明と手順で、availability zoneの表記を「アベイラビリティゾーン」または「AZ」に統一しました。
MSK Provisioned PrivateLink前提手順の更新 tidb-cloud/setup-aws-msk-provisioned-private-link-service.md	AWS Account IDとAZ IDの取得手順を具体化し、MSK Provisioned接続の選択手順を追加しました。ブローカー数の表記も統一しました。

Estimated code review effort: 1 (Trivial) | ~3 minutes

Merge Risk: 🟡 Moderate · up to 7bea7

The AWS setup documentation currently gives contradictory guidance about placing subnets across availability zones, which could lead users to misconfigure AZ matching and fail to connect to TiDB Cloud Premium. Correct the instruction before merging.

Suggested reviewers: invalid-email-address

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly identifies the main change: translating residual English “availability zone” text in Japanese prose.
Description check	✅ Passed	The description explains the affected files, scope, exclusions, version, and AI involvement. The related-link fields are blank, but this is non-critical because the changes and rationale are clearly d…

Full details: Docstring Coverage

Explanation

No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0 files. (3 skipped: 3 unsupported.)

Full details: Description check

Explanation

The description explains the affected files, scope, exclusions, version, and AI involvement. The related-link fields are blank, but this is non-critical because the changes and rationale are clearly documented.

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix-az-untranslated-residual-english

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[coderabbitai]

Actionable comments posted: 1

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: d966a30f-7b4e-4691-8319-486942338b84

📥 Commits

Reviewing files that changed from the base of the PR and between a349332 and 7bea715.

📒 Files selected for processing (3)

• tidb-cloud/architecture-concepts.md
• tidb-cloud/premium/connect-to-premium-via-aws-private-endpoint.md
• tidb-cloud/setup-aws-msk-provisioned-private-link-service.md

Included review availability: Your plan provides up to 4 included reviews per hour; 0 remain after this review.