zsh-autosuggestions, zsh-syntax-highlighting: the plugins as packages and one line each

The distribution packages both, so they are installed as packages rather than cloned or
vendored (novox/hq ADR 0205). Each contributes the line that loads the package's own
copy, from the path the Arch package installs, to a slot of the login shell's block
(ADR 0204). Syntax highlighting goes in last, as its upstream asks.

modules/zsh-autosuggestions/module.json

@@ -0,0 +1,21 @@
+{
+  "module": "zsh-autosuggestions",
+  "version": "1",
+  "capabilities": [
+    "package-manager"
+  ],
+  "shell": [
+    {
+      "for": "zsh",
+      "slot": "normal",
+      "code": "# Suggestions from history as you type, from the distribution's package.\n[[ ! -f /usr/share/zsh/plugins/zsh-autosuggestions/zsh-autosuggestions.zsh ]] || source /usr/share/zsh/plugins/zsh-autosuggestions/zsh-autosuggestions.zsh\n"
+    }
+  ],
+  "resources": [
+    {
+      "id": "package",
+      "type": "package",
+      "package": "zsh-autosuggestions"
+    }
+  ]
+}

modules/zsh-syntax-highlighting/module.json

@@ -0,0 +1,21 @@
+{
+  "module": "zsh-syntax-highlighting",
+  "version": "1",
+  "capabilities": [
+    "package-manager"
+  ],
+  "shell": [
+    {
+      "for": "zsh",
+      "slot": "last",
+      "code": "# Syntax highlighting of the command line, from the distribution's package. Last, as upstream asks:\n# it wraps every widget defined before it.\n[[ ! -f /usr/share/zsh/plugins/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh ]] || source /usr/share/zsh/plugins/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh\n"
+    }
+  ],
+  "resources": [
+    {
+      "id": "package",
+      "type": "package",
+      "package": "zsh-syntax-highlighting"
+    }
+  ]
+}