feat(skills): add github-issue-creator skill (#20709)

.gemini/skills/github-issue-creator/SKILL.md

@@ -0,0 +1,76 @@
+---
+name: github-issue-creator
+description:
+  Use this skill when asked to create a GitHub issue. It handles different issue
+  types (bug, feature, etc.) using repository templates and ensures proper
+  labeling.
+---
+
+# GitHub Issue Creator
+
+This skill guides the creation of high-quality GitHub issues that adhere to the
+repository's standards and use the appropriate templates.
+
+## Workflow
+
+Follow these steps to create a GitHub issue:
+
+1.  **Identify Issue Type**: Determine if the request is a bug report, feature
+    request, or other category.
+
+2.  **Locate Template**: Search for issue templates in
+    `.github/ISSUE_TEMPLATE/`.
+    - `bug_report.yml`
+    - `feature_request.yml`
+    - `website_issue.yml`
+    - If no relevant YAML template is found, look for `.md` templates in the same
+      directory.
+
+3.  **Read Template**: Read the content of the identified template file to
+    understand the required fields.
+
+4.  **Draft Content**: Draft the issue title and body/fields.
+    - If using a YAML template (form), prepare values for each `id` defined in
+      the template.
+    - If using a Markdown template, follow its structure exactly.
+    - **Default Label**: Always include the `🔒 maintainer only` label unless the
+      user explicitly requests otherwise.
+
+5.  **Create Issue**: Use the `gh` CLI to create the issue.
+    - **CRITICAL:** To avoid shell escaping and formatting issues with
+      multi-line Markdown or complex text, ALWAYS write the description/body to
+      a temporary file first.
+
+    **For Markdown Templates or Simple Body:**
+    ```bash
+    # 1. Write the drafted content to a temporary file
+    # 2. Create the issue using the --body-file flag
+    gh issue create --title "Succinct title" --body-file <temp_file_path> --label "🔒 maintainer only"
+    # 3. Remove the temporary file
+    rm <temp_file_path>
+    ```
+
+    **For YAML Templates (Forms):**
+    While `gh issue create` supports `--body-file`, YAML forms usually expect
+    key-value pairs via flags if you want to bypass the interactive prompt.
+    However, the most reliable non-interactive way to ensure formatting is
+    preserved for long text fields is to use the `--body` or `--body-file` if the
+    form has been converted to a standard body, OR to use the `--field` flags
+    for YAML forms.
+
+    *Note: For the `gemini-cli` repository which uses YAML forms, you can often
+    submit the content as a single body if a specific field-based submission is
+    not required by the automation.*
+
+6.  **Verify**: Confirm the issue was created successfully and provide the link
+    to the user.
+
+## Principles
+
+- **Clarity**: Titles should be descriptive and follow project conventions.
+- **Defensive Formatting**: Always use temporary files with `--body-file` to
+  prevent newline and special character issues.
+- **Maintainer Priority**: Default to internal/maintainer labels to keep the
+  backlog organized.
+- **Completeness**: Provide all requested information (e.g., version info,
+  reproduction steps).