Add repo-standardizer skill: polish any GitHub repo surface (#2715)

* Add repo-standardizer skill: polish any GitHub repo surface

* fix(skill): remove non-string metadata and fix template README refs for vally lint

* docs(skill): drop markdown relative links from README language-switcher example

Vally valid-refs flagged ./README.md and ./README.zh.md as missing file
references; they are generated artifacts, not skill files. Keep the
example as plain text to satisfy the linter.

* fix(template): add missing language switcher to English README template

Align with README.zh.md template and SKILL.md switcher convention:
current language as plain text, other languages as relative links.

---------

Co-authored-by: programmingWTF <programmingWTF@users.noreply.github.com>

skills/repo-standardizer/templates/issue-form-bug.yml

@@ -0,0 +1,53 @@
+name: Bug report
+description: Report a bug to help us improve
+title: "[Bug]: "
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to fill out this bug report!
+  - type: textarea
+    id: description
+    attributes:
+      label: Describe the bug
+      description: A clear and concise description of what the bug is.
+      placeholder: Tell us what happened
+    validations:
+      required: true
+  - type: textarea
+    id: reproduction
+    attributes:
+      label: Steps to reproduce
+      description: How can we reproduce the issue?
+      placeholder: |
+        1. Go to '...'
+        2. Click on '...'
+        3. See error
+    validations:
+      required: true
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected behavior
+      description: What did you expect to happen?
+    validations:
+      required: true
+  - type: textarea
+    id: environment
+    attributes:
+      label: Environment
+      description: Please complete the following information.
+      value: |
+        - OS: [e.g. Ubuntu 24.04, macOS 14, Windows 11]
+        - Version / commit: [e.g. v1.2.3 / abc1234]
+        - Runtime: [e.g. Node 22, Python 3.12]
+    validations:
+      required: false
+  - type: checkboxes
+    id: terms
+    attributes:
+      label: Confirmation
+      options:
+        - label: I have searched for existing issues and this is not a duplicate
+          required: true