concouseのweb uiをカスタマイズしたい

今、concouse uiのweb uiの部分をカスタマイズしております。
しかし、型が厳密に決まっており、思うようにいきません。

どの部分を改修いているかと言いますと、下記の画像のパイプラインごとにタグを登録する機能を実装しようとしています。
挙動としてはテキストフィールドにタグ名を入力したら「タグを追加」というボタンを押したら後、タグが追加されるようにしたいです。

下記のような機能はtodoアプリのようにテキストを入力して、ボタンを押したらリストにデータが入っていくソースです。

elm
1module Main exposing (main)

2
3import Browser
4import Html exposing (..)

5import Html.Attributes exposing (..)

6import Html.Events exposing (onClick, onInput)

7
8import Debug exposing (log)
9
10main =
11  Browser.sandbox { init = init, update = update, view = view }
12
13--Model
14
15-- Todoのリストの構造
16type alias Todo =
17  { description : String
18  }
19
20-- Todoリストそのもの型
21-- List型っていうこと
22type alias Model =
23  { todos : List Todo
24  , input : Todo
25  }
26
27init : Model
28init =
29  { todos = []
30  , input = Todo ""
31  }
32
33type Msg = Add | Change String
34
35--Update
36
37update : Msg -> Model -> Model
38update msg model =
39  case msg of
40    Add ->
41      { model | todos = model.input :: model.todos }
42    Change str ->
43      { model | input = Todo str }
44
45-- View
46
47view : Model -> Html Msg
48view model =
49  div []
50    [ input [ type_ "text", placeholder "What will you do?", onInput Change] []
51    , button [ onClick Add ] [ text "Add" ]
52    , ul [] (List.map viewLi model.todos)
53    ]
54
55viewLi : Todo -> Html Msg
56viewLi todo =
57  li [] [ text todo.description ]
58

上記の部分を少し改修して、下記の「Group.elm」に入れたら、intellijで「Type mismatch. Required: Html Message Found: Html Msg。」というメッセージが出てしまいました。
concourseを改修して、下記のようにしたら出ます。

■Group.elm

elm
1pipelineCardView :
2    { a | userState : UserState, favoritedPipelines : Set Concourse.DatabaseID }
3    ->
4        { b
5            | dragState : DragState
6            , dropState : DropState
7            , now : Maybe Time.Posix
8            , hovered : HoverState.HoverState
9            , pipelineRunningKeyframes : String
10            , pipelinesWithResourceErrors : Set ( String, String )
11            , pipelineLayers : Dict ( String, String ) (List (List Concourse.JobIdentifier))
12            , pipelineJobs : Dict ( String, String ) (List Concourse.JobIdentifier)
13            , jobs : Dict ( String, String, String ) Concourse.Job
14        }
15    -> PipelinesSection
16    ->
17        { bounds : PipelineGrid.Bounds
18        , pipeline : Pipeline
19        }
20    -> String
21    -> Html Message
22pipelineCardView session params section { bounds, pipeline } teamName =
23    Html.div
24        ([ class "pipeline-wrapper"
25         , style "position" "absolute"
26         , style "transform"
27            ("translate("
28                ++ String.fromFloat bounds.x
29                ++ "px,"
30                ++ String.fromFloat bounds.y
31                ++ "px)"
32            )
33         , style
34            "width"
35            (String.fromFloat bounds.width
36                ++ "px"
37            )
38         , style "height"
39            (String.fromFloat bounds.height
40                ++ "px"
41            )
42         , onMouseOver <|
43            Hover <|
44                Just <|
45                    PipelineWrapper
46                        { pipelineName = pipeline.name
47                        , teamName = pipeline.teamName
48                        }
49         , onMouseOut <| Hover Nothing
50         ]
51            ++ (if params.dragState /= NotDragging then
52                    [ style "transition" "transform 0.2s ease-in-out" ]
53
54                else
55                    []
56               )
57            ++ (let
58                    hoverStyle id =
59                        if
60                            (id.pipelineName == pipeline.name)
61                                && (id.teamName == pipeline.teamName)
62                        then
63                            [ style "z-index" "1" ]
64
65                        else
66                            []
67                in
68                case HoverState.hoveredElement params.hovered of
69                    Just (JobPreview _ jobID) ->
70                        hoverStyle jobID
71
72                    Just (PipelineWrapper pipelineID) ->
73                        hoverStyle pipelineID
74
75                    _ ->
76                        []
77               )
78        )
79        [ Html.div
80            ([ class "card"
81             , style "width" "100%"
82             , style "height" "100%"
83             , attribute "data-pipeline-name" pipeline.name
84             ]
85                ++ (if section == AllPipelinesSection && not pipeline.stale then
86                        [ attribute
87                            "ondragstart"
88                            "event.dataTransfer.setData('text/plain', '');"
89                        , draggable "true"
90                        , on "dragstart"
91                            (Json.Decode.succeed (DragStart pipeline.teamName pipeline.name))
92                        , on "dragend" (Json.Decode.succeed DragEnd)
93                        ]
94
95                    else
96                        []
97                   )
98                ++ (if params.dragState == Dragging pipeline.teamName pipeline.name then
99                        [ style "width" "0"
100                        , style "margin" "0 12.5px"
101                        , style "overflow" "hidden"
102                        ]
103
104                    else
105                        []
106                   )
107                ++ (if params.dropState == DroppingWhileApiRequestInFlight teamName then
108                        [ style "opacity" "0.45", style "pointer-events" "none" ]
109
110                    else
111                        [ style "opacity" "1" ]
112                   )
113            )
114            [ Pipeline.pipelineView
115                { now = params.now
116                , pipeline = pipeline
117                , resourceError =
118                    params.pipelinesWithResourceErrors
119                        |> Set.member ( pipeline.teamName, pipeline.name )
120                , existingJobs =
121                    params.pipelineJobs
122                        |> Dict.get ( pipeline.teamName, pipeline.name )
123                        |> Maybe.withDefault []
124                        |> List.filterMap (lookupJob params.jobs)
125                , layers =
126                    params.pipelineLayers
127                        |> Dict.get ( pipeline.teamName, pipeline.name )
128                        |> Maybe.withDefault []
129                        |> List.map (List.filterMap <| lookupJob params.jobs)
130                , hovered = params.hovered
131                , pipelineRunningKeyframes = params.pipelineRunningKeyframes
132                , userState = session.userState
133                , favoritedPipelines = session.favoritedPipelines
134                , section = section
135                }
136                , Html.div
137                    (class "tag-list" :: Styles.tagList)
138                    [
139                        --ul [] (List.map viewLi model.todos)
140                        Html.div
141                        [class "tag-list-tag"]
142                        [
143                            Html.text "#tag1"
144                        ]
145                    ]
146                , Html.div
147                    (class "tag-list" :: Styles.tagList)
148                    [
149                        Html.div
150                            (class "tag-input-bord" :: Styles.tagInputBord)
151                            [
152                                Html.div
153                                [class "tag-input-bord-wrapper"]
154                                [
155                                    Html.input
156                                    ([
157                                    placeholder "例）tag1"
158                                    ])
159                                    []
160                                ]
161                            ],
162                        Html.button
163                            (class "tag-list-button" :: Styles.tagListButton)
164                            [
165                                Html.text "タグを追加"
166                            ]
167                    ]
168            ]
169        ]