feat(config): add issue templates for Epics, User Stories, and Subtasks (#4)

Reviewed-on: #4

.gitea/ISSUE_TEMPLATE/epic.md

@@ -0,0 +1,46 @@
+---
+name: "Epic"
+about: "A large initiative or feature that consists of multiple User Stories or Subtasks"
+title: "[Epic] <Epic title>"
+labels: ["Type/Epic"]
+---
+
+## 🧩 Epic Summary
+Provide a clear summary of what this Epic aims to achieve.
+
+---
+
+## 🎯 Goals
+- [ ] Goal 1
+- [ ] Goal 2
+- [ ] Goal 3
+
+---
+
+## 📋 Description
+Describe the high-level context, purpose, and expected outcome of this Epic.
+
+---
+
+## 🧵 Related User Stories / Subtasks
+Link to related issues here:
+- [ ] #<user-story-1>
+- [ ] #<user-story-2>
+- [ ] #<subtask-1>
+
+---
+
+## 📅 Milestone / Timeline
+If applicable, note any key dates or milestones:
+- Target Start:
+- Target Completion:
+
+---
+
+## ⚠️ Risks / Dependencies
+List any major risks or dependencies that could affect delivery.
+
+---
+
+## ✅ Acceptance Criteria
+Define the success metrics or completion definition for the Epic.