Add Gitea Actions workflows, CI config, and docs

.gitea/ISSUE_TEMPLATE/auth_security.yml

@@ -0,0 +1,59 @@
+name: Authentication & Security
+about: Report a security concern or suggest a security enhancement
+title: "[Security] "
+labels:
+  - security
+body:
+  - type: markdown
+    attributes:
+      value: |
+        **For actual vulnerabilities, do NOT use this template.**
+        Email security@hiddenden.cafe instead. See SECURITY.md.
+
+  - type: textarea
+    id: summary
+    attributes:
+      label: Summary
+      description: Summary of the authentication / security concern or enhancement.
+    validations:
+      required: true
+
+  - type: textarea
+    id: description
+    attributes:
+      label: Description
+      description: Detailed description (vulnerability, misconfiguration, missing control).
+    validations:
+      required: true
+
+  - type: textarea
+    id: affected
+    attributes:
+      label: Affected Components
+      description: List services, endpoints, or libraries affected.
+
+  - type: textarea
+    id: reproduction
+    attributes:
+      label: Reproduction / PoC
+      description: Steps to reproduce. Do NOT include exploit payloads in public issues.
+
+  - type: textarea
+    id: remediation
+    attributes:
+      label: Suggested Remediation
+      description: Concrete steps to fix, including links to standards or CVE info.
+
+  - type: textarea
+    id: references
+    attributes:
+      label: References
+      description: Links to auth standards (OAuth2, OIDC), encryption recommendations, or policy.
+
+  - type: checkboxes
+    id: checklist
+    attributes:
+      label: Checklist
+      options:
+        - label: Confirmed requirement with security lead
+        - label: Unit/integration tests planned for fix