make clause of widget to support displaying global_val

[PipeYume]

Summary

Features "make clause of widget to support displaying global_val and other custom entries"

Purpose of change

Allow widgets to display anything you want to display.

If you have a custom variable and you want to display it in a widget, you just need to use the clause and set parse_tags to true.

At this point, the values such as <global_val:XXX> in the 'text' will be converted to the corresponding text.

Describe the solution

In widget.cpp, add this to allow to parse tags.

        if( wp->should_parse_tags ) {
            parse_tags( txt, get_player_character(), get_player_character() );
        }

Also, in npctalk.cpp, I modify parse_tags function to make it support color tags:
Now, it will not remove the color tags automatically.

Describe alternatives you've considered

None.

Testing

I didn't find where to place a ui test, so I place it here.

[
  {
    "copy-from": "legacy_classic_sidebar",
    "type": "widget",
    "id": "legacy_classic_sidebar",
    "extend": { "widgets": [ "widget_ui_test" ] }
  },
  {
    "id": "widget_ui_test",
    "type": "widget",
    "label": "Test",
    "style": "text",
    "height": 1,
    "clauses": [ { "id": "clause_test", "text": "<global_val:display_text>", "parse_tags": true } ]
  },
  {
    "id": "EOC_widget_ui_test",
    "//": "",
    "type": "effect_on_condition",
    "global": true,
    "recurrence": 1,
    "effect": [
      {
        "if": { "or": [ { "not": { "math": [ "test_count" ] } }, { "math": [ "test_count", ">=", "4" ] } ] },
        "then": { "math": [ "test_count", "=", "0" ] }
      },
      { "math": [ "test_count", "++" ] },
      {
        "switch": { "math": [ "test_count" ] },
        "cases": [
          { "case": 1, "effect": { "set_string_var": "red", "target_var": { "context_val": "color" } } },
          { "case": 2, "effect": { "set_string_var": "white", "target_var": { "context_val": "color" } } },
          { "case": 3, "effect": { "set_string_var": "yellow", "target_var": { "context_val": "color" } } },
          { "case": 4, "effect": { "set_string_var": "green", "target_var": { "context_val": "color" } } }
        ]
      },
      {
        "set_string_var": "<color_white>[<color_<context_val:color>>]<global_val:test_count>[</color>]</color>",
        "target_var": { "global_val": "display_text" },
        "parse_tags": true
      }
    ]
  }
]

It seems like this:
https://github.com/CleverRaven/Cataclysm-DDA/assets/81861009/3b53d41b-8541-460e-bbc7-9ed02d4c073e

Additional context

[github-actions]

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