refactor: move stack assets and wire in mailhog

ToolboxStack/output/toolbox-base/aqua.yaml

@@ -0,0 +1,18 @@
+version: 1.0.0
+registries:
+  - type: standard
+    ref: v4.200.0
+packages:
+  - name: cli/cli@v2.82.1
+  - name: jesseduffield/lazygit@v0.55.1
+  - name: direnv/direnv@v2.37.1
+  - name: dandavison/delta@0.18.2
+  - name: ajeetdsouza/zoxide@v0.9.8
+  - name: casey/just@1.43.0
+  - name: mikefarah/yq@v4.48.1
+  - name: ducaale/xh@v0.25.0
+  - name: rs/curlie@v1.8.2
+  - name: twpayne/chezmoi@v2.66.1
+  - name: mvdan/sh@v3.12.0
+  - name: koalaman/shellcheck@v0.11.0
+  - name: hadolint/hadolint@v2.14.0