chore: add Go version lint check, modernize issue templates (#557)

- Add go.mod version check in lint workflow (fails if go directive != 1.20)
- Add golang.org/x/sys to dependabot ignore list (newer versions require Go 1.21+)
- Fix golang.org/x/text ignore comment
- Migrate issue templates from markdown to YAML forms:
- Update PR template (dev → main, add go.mod checklist item)
- Update .gitignore for YAML issue templates

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Documentation
+    url: https://github.com/moonD4rk/HackBrowserData/tree/main/rfcs
+    about: Read the RFCs for architecture and encryption details.