docs: simplify the homepage and public repository layout

.github/ISSUE_TEMPLATE/bug-report.yml

@@ -0,0 +1,72 @@
+name: Bug report / 缺陷报告
+description: Report reproducible incorrect behavior / 报告可复现的异常行为
+title: "[Bug] "
+labels:
+  - bug
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Remove passwords, tokens, private keys, databases, private network details, and real IR data from all text and attachments.
+        请从文字和附件中移除密码、Token、证书私钥、数据库、私有网络信息和真实红外数据。
+  - type: textarea
+    id: description
+    attributes:
+      label: Problem description / 问题描述
+      description: What happened, and which component was involved? / 发生了什么，涉及哪个组件？
+    validations:
+      required: true
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps to reproduce / 复现步骤
+      placeholder: "1. ...\n2. ...\n3. ..."
+    validations:
+      required: true
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected result / 预期结果
+    validations:
+      required: true
+  - type: textarea
+    id: actual
+    attributes:
+      label: Actual result / 实际结果
+    validations:
+      required: true
+  - type: input
+    id: version
+    attributes:
+      label: Version or commit / 版本或提交
+      placeholder: v1.2.6 or commit SHA
+    validations:
+      required: true
+  - type: dropdown
+    id: component
+    attributes:
+      label: Component / 组件
+      multiple: true
+      options:
+        - Firmware / 固件
+        - Cloud backend / 云端后端
+        - Web frontend / 网页前端
+        - MQTT configuration / MQTT 配置
+        - IR learner / 红外学习工具
+        - Hardware or PCB / 硬件或 PCB
+        - Documentation / 文档
+        - Not sure / 不确定
+    validations:
+      required: true
+  - type: textarea
+    id: logs
+    attributes:
+      label: Sanitized logs / 脱敏日志
+      render: shell
+  - type: checkboxes
+    id: sensitive-data
+    attributes:
+      label: Sensitive data check / 敏感信息确认
+      options:
+        - label: I removed all credentials, private keys, databases, private network details, and real IR data. / 我已移除所有凭据、私钥、数据库、私有网络信息和真实红外数据。
+          required: true

.github/ISSUE_TEMPLATE/config.yml

@@ -1,8 +1,8 @@
 blank_issues_enabled: false
 contact_links:
-  - name: Security vulnerability
+  - name: Security vulnerability / 安全漏洞
     url: https://github.com/nobodycareme/remote-ac-controller/security/advisories/new
-    about: Do NOT open a public issue. Report vulnerabilities privately here.
-  - name: Question / usage help
-    url: https://github.com/nobodycareme/remote-ac-controller/discussions
-    about: Ask usage questions in Discussions rather than the issue tracker.
+    about: Report security issues privately. 安全问题请私下报告，不要公开提交。
+  - name: Usage help / 使用帮助
+    url: https://github.com/nobodycareme/remote-ac-controller/blob/main/SUPPORT.md
+    about: Check the support routes before opening an issue. 提交前请先查看支持入口。

.github/ISSUE_TEMPLATE/documentation.yml

@@ -0,0 +1,49 @@
+name: Documentation issue / 文档问题
+description: Report missing, incorrect, or unclear documentation / 报告缺失、错误或不清楚的文档
+title: "[Docs] "
+labels:
+  - documentation
+body:
+  - type: input
+    id: path
+    attributes:
+      label: Document path or link / 文档路径或链接
+      placeholder: docs/English/deployment.md
+    validations:
+      required: true
+  - type: dropdown
+    id: issue-type
+    attributes:
+      label: Issue type / 问题类型
+      options:
+        - Incorrect information / 信息错误
+        - Missing information / 信息缺失
+        - Unclear instructions / 说明不清
+        - Broken link or formatting / 链接或格式问题
+        - Translation mismatch / 翻译不一致
+    validations:
+      required: true
+  - type: dropdown
+    id: language
+    attributes:
+      label: Language / 语言版本
+      options:
+        - Chinese / 中文
+        - English / 英文
+        - Both / 两者
+    validations:
+      required: true
+  - type: textarea
+    id: proposal
+    attributes:
+      label: Suggested change / 建议修改
+      description: Quote only the minimum context needed. / 只引用必要的上下文。
+    validations:
+      required: true
+  - type: checkboxes
+    id: sensitive-data
+    attributes:
+      label: Sensitive data check / 敏感信息确认
+      options:
+        - label: I removed credentials, private keys, databases, private network details, and real IR data. / 我已移除凭据、私钥、数据库、私有网络信息和真实红外数据。
+          required: true

.github/ISSUE_TEMPLATE/feature-request.yml

@@ -0,0 +1,48 @@
+name: Feature request / 功能建议
+description: Propose a change based on a concrete use case / 基于具体场景提出改进
+title: "[Feature] "
+body:
+  - type: textarea
+    id: use-case
+    attributes:
+      label: Use case / 使用场景
+      description: What are you trying to accomplish? / 你希望完成什么？
+    validations:
+      required: true
+  - type: textarea
+    id: limitation
+    attributes:
+      label: Current limitation / 当前限制
+      description: What prevents that workflow today? / 当前是什么阻碍了这个流程？
+    validations:
+      required: true
+  - type: textarea
+    id: proposal
+    attributes:
+      label: Proposed behavior / 建议行为
+      description: Describe the smallest useful change. / 描述最小且有用的改动。
+    validations:
+      required: true
+  - type: dropdown
+    id: component
+    attributes:
+      label: Affected component / 影响组件
+      multiple: true
+      options:
+        - Firmware / 固件
+        - Cloud backend / 云端后端
+        - Web frontend / 网页前端
+        - MQTT configuration / MQTT 配置
+        - IR learner / 红外学习工具
+        - Hardware or PCB / 硬件或 PCB
+        - Documentation / 文档
+        - Not sure / 不确定
+    validations:
+      required: true
+  - type: checkboxes
+    id: sensitive-data
+    attributes:
+      label: Sensitive data check / 敏感信息确认
+      options:
+        - label: This request contains no credentials, private keys, databases, private network details, or real IR data. / 本建议不含凭据、私钥、数据库、私有网络信息或真实红外数据。
+          required: true

.github/pull_request_template.md

@@ -0,0 +1,35 @@
+# Pull Request
+
+## Summary
+
+<!-- What changes, and why? -->
+
+## Scope
+
+<!-- List the components and files intentionally changed. -->
+
+## Validation
+
+<!-- List the exact commands or manual checks that were run. -->
+
+- [ ] Tests relevant to this change passed
+- [ ] A skipped or unavailable check is explained above
+
+## Security
+
+- [ ] No production credentials, tokens, passwords, private keys, certificates, or databases are included
+- [ ] No real air-conditioner IR data is included
+- [ ] Logs, screenshots, and examples are sanitized
+- [ ] Security-sensitive behavior is described for reviewers
+
+## Documentation
+
+- [ ] User-facing behavior is documented, or this change needs no documentation
+- [ ] Chinese and English documents are synchronized where both exist
+- [ ] Added and changed links were checked
+
+## Release impact
+
+- [ ] Version impact is stated: none, patch, minor, or major
+- [ ] Tag and Release asset impact is stated
+- [ ] Any migration or compatibility impact is described

.github/workflows/ci.yml

@@ -1013,6 +1013,9 @@ jobs:
         with:
           python-version: '3.12'
 
+      - name: Install documentation validation dependencies
+        run: python3 -m pip install "PyYAML>=6.0,<7"
+
       - name: Documentation parity (every first-party doc paired CN<->EN)
         run: python3 tools/check-doc-parity.py
 
@@ -1037,6 +1040,9 @@ jobs:
         with:
           python-version: '3.12'
 
+      - name: Install documentation validation dependencies
+        run: python3 -m pip install "PyYAML>=6.0,<7"
+
       - name: No broken first-party relative links
         run: python3 tools/check-doc-links.py
 
@@ -1134,6 +1140,9 @@ jobs:
         uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - name: Install documentation validation dependencies
+        run: python3 -m pip install "PyYAML>=6.0,<7"
+
       - name: Verify v1.2.5 public documentation contract
         run: |
           python3 tools/check-public-docs.py