Updated project README to include references to the new security policy.

Moved the project's code of conduct out of the contributions guide and into the appropriate policy file.

Updated the contribution guide to follow the NetBox project format.

Added various issue templates based on the NetBox project formats but updated for PDA.

Added additional GitHub workflows to handle stale and closed issue and PR management.

Removed legacy stale issue workflow that was not in use.

.github/ISSUE_TEMPLATE/housekeeping.yaml

@@ -0,0 +1,24 @@
+---
+name: 🏡 Housekeeping
+description: A change pertaining to the codebase itself (developers only)
+labels: ["type: housekeeping"]
+body:
+  - type: markdown
+    attributes:
+      value: >
+        **NOTE:** This template is for use by maintainers only. Please do not submit
+        an issue using this template unless you have been specifically asked to do so.
+  - type: textarea
+    attributes:
+      label: Proposed Changes
+      description: >
+        Describe in detail the new feature or behavior you'd like to propose.
+        Include any specific changes to work flows, data models, or the user interface.
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Justification
+      description: Please provide justification for the proposed change(s).
+    validations:
+      required: true