feat: add mercurial state (#6745)

.github/config-schema.json

@@ -892,6 +892,26 @@
         }
       ]
     },
+    "hg_state": {
+      "default": {
+        "bisect": "BISECTING",
+        "disabled": true,
+        "format": "\\([$state]($style)\\) ",
+        "graft": "GRAFTING",
+        "histedit": "HISTEDITING",
+        "merge": "MERGING",
+        "rebase": "REBASING",
+        "shelve": "SHELVING",
+        "style": "bold yellow",
+        "transplant": "TRANSPLANTING",
+        "update": "UPDATING"
+      },
+      "allOf": [
+        {
+          "$ref": "#/definitions/HgStateConfig"
+        }
+      ]
+    },
     "hostname": {
       "default": {
         "aliases": {},
@@ -4232,6 +4252,56 @@
       },
       "additionalProperties": false
     },
+    "HgStateConfig": {
+      "type": "object",
+      "properties": {
+        "merge": {
+          "default": "MERGING",
+          "type": "string"
+        },
+        "rebase": {
+          "default": "REBASING",
+          "type": "string"
+        },
+        "update": {
+          "default": "UPDATING",
+          "type": "string"
+        },
+        "bisect": {
+          "default": "BISECTING",
+          "type": "string"
+        },
+        "shelve": {
+          "default": "SHELVING",
+          "type": "string"
+        },
+        "graft": {
+          "default": "GRAFTING",
+          "type": "string"
+        },
+        "transplant": {
+          "default": "TRANSPLANTING",
+          "type": "string"
+        },
+        "histedit": {
+          "default": "HISTEDITING",
+          "type": "string"
+        },
+        "style": {
+          "default": "bold yellow",
+          "type": "string"
+        },
+        "format": {
+          "default": "\\([$state]($style)\\) ",
+          "type": "string"
+        },
+        "disabled": {
+          "default": true,
+          "type": "boolean"
+        }
+      },
+      "additionalProperties": false
+    },
     "HostnameConfig": {
       "type": "object",
       "properties": {