feat: add GitHub issue templates

[mnriem]

Fixes #1654 - Add GitHub issue templates for agents, bugs, features, and extensions

[Copilot]

Pull request overview

This PR adds GitHub issue templates to improve the issue reporting and submission workflow for the Spec Kit repository. The templates provide structured forms for bug reports, feature requests, agent integration requests, and extension submissions, making it easier for contributors to provide relevant information.

Changes:

• Added 4 issue template forms (bug report, feature request, agent request, extension submission)
• Added configuration file to disable blank issues and provide helpful links
• Templates include agent selection dropdowns and structured fields for better triage

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
.github/ISSUE_TEMPLATE/bug_report.yml	Structured form for reporting bugs with fields for reproduction steps, version info, and agent selection
.github/ISSUE_TEMPLATE/feature_request.yml	Form for feature requests with problem statement, solution proposal, and use cases
.github/ISSUE_TEMPLATE/agent_request.yml	Template for requesting new AI agent support with technical details and example commands
.github/ISSUE_TEMPLATE/extension_submission.yml	Comprehensive form for submitting extensions to the Spec Kit catalog with testing checklist
.github/ISSUE_TEMPLATE/config.yml	Configuration to disable blank issues and provide links to documentation and community resources

Comments suppressed due to low confidence (1)

.github/ISSUE_TEMPLATE/config.yml:12

• The emoji character appears to be corrupted or using an invalid encoding. It should be a valid emoji like 🤝 (which already exists later in the text) to maintain consistency with the other entries.

  - name: �🤝 Contributing Guide

---

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

.github/ISSUE_TEMPLATE/config.yml:12

• The emoji character at the start of this line is corrupted and displays as a replacement character (�). This should likely be a handshake emoji (🤝) which is already present in the text, making it redundant, or possibly a different emoji like 👥 for community contribution.

  - name: 🤝 Contributing Guide

---

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