maint/dev ~ add git mailmap (improves commit history accuracy)

- `git shortlog -se -n --all` # review all commit authors/emails
- `git shortlog -se -n --all --no-merges` # ... same with merge commit statistics excluded

- ref: [`git` ~ display project devs](https://stackoverflow.com/questions/9597410/list-all-developers-on-a-project-in-git) @@ <https://archive.is/ZbVJP>

.mailmap

@@ -0,0 +1,10 @@
+## spell-checker:disable
+Alex Lyon <[email protected]> <[email protected]>
+Ingvar Stepanyan <[email protected]> <[email protected]>
+Sylvestre Ledru <[email protected]> <[email protected]>
+#
+dependabot[bot] <dependabot[bot]@users.noreply.github.com> <49699333+dependabot[bot]@users.noreply.github.com>
+dependabot[bot] <dependabot[bot]@users.noreply.github.com> <27856297+dependabot-preview[bot]@users.noreply.github.com>
+dependabot[bot] <dependabot[bot]@users.noreply.github.com> <dependabot-preview[bot]@users.noreply.github.com>
+#
+renovate[bot] <renovate[bot]@users.noreply.github.com> <29139614+renovate[bot]@users.noreply.github.com>