Add Dependabot and a private disclosure channel to SECURITY.md

.github/dependabot.yml

@@ -0,0 +1,25 @@
+version: 2
+updates:
+  - package-ecosystem: "pip"
+    directory: "/packages/pyxle-auth"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5
+
+  - package-ecosystem: "pip"
+    directory: "/packages/pyxle-db"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5
+
+  - package-ecosystem: "pip"
+    directory: "/packages/pyxle-mail"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5
+
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5

SECURITY.md

@@ -14,7 +14,12 @@ Both packages are pre-1.0: we fix forward rather than backporting.
 
 **Please do not open a public issue for security reports.**
 
-Email **security@pyxle.dev** with:
+Report privately through either channel:
+
+- **GitHub private advisory (preferred):** [Report a vulnerability](https://github.com/pyxle-dev/pyxle-plugins/security/advisories/new) — this opens a private thread with the maintainers.
+- **Email:** **security@pyxle.dev**
+
+Please include:
 
 - The affected package and version.
 - A description of the issue and its impact.