Import upstream v0.16.22, stripped

Upstream commit: 474dd0229cb20cf513036619781ed97bd8073c3f
Enterprise-only files removed or emptied: 63
Enterprise-only snippets removed: 117 in 50 files
Dangling module declarations removed: 5
Cargo edits turning enterprise off: 14
Verification: clean
Enterprise feature gates left for rebuilt features: 19 in 18 files

Produced by tools/fork/strip.py. The full report is in docs/fork/strip-reports/ on main.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,17 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Report an Issue
+    url: https://support.stalw.art
+    about: Report a potential bug at support.stalw.art. Confirmed bugs will be converted to Issues. Sign in with your GitHub account.
+  - name: Questions & Support
+    url: https://support.stalw.art
+    about: Get help with configuration, troubleshooting, or general questions at support.stalw.art. Sign in with your GitHub account.
+  - name: Feature Requests
+    url: https://support.stalw.art
+    about: Suggest new features or improvements at support.stalw.art. Sign in with your GitHub account.
+  - name: Join Stalwart's Reddit
+    url: https://www.reddit.com/r/stalwartlabs
+    about: Join our subreddit for community discussions and release announcements.
+  - name: Join Stalwart's Discord
+    url: https://discord.com/servers/stalwart-923615863037390889
+    about: Join our Discord server for community chat and release announcements.