chore(aiwg): adopt shared BT6 maintainer workflow (#148)

* docs(policy): allow low-impact contributor courtesy cleanup

* chore(aiwg): migrate to shared BT6 maintainer plugin

* chore: reconcile delivery validation

.aiwg/plugins/bt6-maintainer/payload/provenance/SOURCE.md

@@ -0,0 +1,28 @@
+# Source provenance
+
+## Upstream source
+
+- Repository: `elder-plinius/T3MP3ST`
+- Source path: `.aiwg/addons/t3mp3st-maintainer/`
+- Source commit: `b192577b5462d2f7388e91c83b4cb2874ab99c03`
+- Source URL: <https://github.com/elder-plinius/T3MP3ST/tree/b192577b5462d2f7388e91c83b4cb2874ab99c03/.aiwg/addons/t3mp3st-maintainer>
+- Source license: GNU Affero General Public License v3.0
+- Source author history for this path: Joseph Magly
+- Generalization repository: `jmagly/bt6-aiwg-plugins`
+
+## Transformation summary
+
+The BT6 version preserves the source addon's queue-audit, exact-SHA PR review,
+issue-stewardship, one-at-a-time merge, linked-issue reconciliation,
+public-input threat assessment, and explicit mutation-authorization concepts.
+
+It replaces fixed T3MP3ST repository, GitHub CLI, branch, validation-command,
+security-contact, and source-path assumptions with a repository profile and
+tracker-authority resolution process. It adds research/support-tool quality
+surfaces, portable namespacing, provider-neutral model roles, configuration
+schema, and standalone plugin delivery metadata.
+
+## License
+
+This derivative is distributed under AGPL-3.0. The repository root `LICENSE`
+contains the full license text.