docs: add issue template for RFCs (#57)

.github/ISSUE_TEMPLATE/rfc.yml

@@ -0,0 +1,77 @@
+name: Request for Comments (RFC)
+description: Feature design and detailed proposals
+title: "RFC: TITLE"
+labels: ["RFC", "triage"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for submitting a RFC. Please add as many details as possible to help further enrich this design.
+  - type: input
+    id: relation
+    attributes:
+      label: Is this related to an existing feature request or issue?
+      description: Please share a link, if applicable
+  - type: dropdown
+    id: area
+    attributes:
+      label: What part of the Cloud Game Development Toolkit does this RFC relate to?
+      options:
+        - Assets
+        - Modules
+        - Playbooks
+        - Samples
+        - Other
+    validations:
+      required: true
+  - type: textarea
+    id: summary
+    attributes:
+      label: Summary
+      description: Please provide an overview in one or two paragraphs
+    validations:
+      required: true
+  - type: textarea
+    id: problem
+    attributes:
+      label: Use case
+      description: Please share the use case and motivation behind this proposal
+    validations:
+      required: true
+  - type: textarea
+    id: proposal
+    attributes:
+      label: Proposal
+      description: Please explain the design in detail, so anyone familiar with the project could implement it
+      placeholder: What the user experience looks like before and after this design?
+    validations:
+      required: true
+  - type: textarea
+    id: scope
+    attributes:
+      label: Out of scope
+      description: Please explain what should be considered out of scope in your proposal
+    validations:
+      required: true
+  - type: textarea
+    id: challenges
+    attributes:
+      label: Potential challenges
+      description: Nothing is perfect. Please share what common challenges, edge cases, unresolved areas, and suggestions on how to mitigate them
+    validations:
+      required: true
+  - type: textarea
+    id: integrations
+    attributes:
+      label: Dependencies and Integrations
+      description: If applicable, please share whether this feature has additional dependencies, and how it might integrate with other parts of this project
+    validations:
+      required: false
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: Alternative solutions
+      description: Please describe what alternative solutions to this use case, if any
+      render: markdown
+    validations:
+      required: false