Replace Python CLI with Gitea issue tracker setup

Switch from a custom CLI ticketing tool to Gitea-native issue tracking.
Add issue templates (bug, feature, task) and a curated initial backlog
of 20 tickets covering project foundation, testing, security, docs,
features, and community maintenance.

.gitea/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,28 @@
+---
+name: "✨ Feature Request"
+about: "Propose a new feature or enhancement."
+title: "[Feature] "
+labels: ["enhancement", "triage"]
+assignees: []
+---
+
+## Problem Statement
+
+<!-- What problem are you trying to solve? Why is this valuable? -->
+
+## Proposed Solution
+
+<!-- Describe the feature or enhancement you'd like to see. -->
+
+## Alternatives Considered
+
+<!-- Are there other ways to solve this? Why did you choose this approach? -->
+
+## Acceptance Criteria
+
+- [ ] <!-- Checkable criteria for when this is "done" -->
+
+## Additional Context
+
+<!-- Screenshots, references, or anything else that helps. -->
+