Addition of FlagInputModal (#1606)

## Description:

The UI for selecting flags differs from other existing UIs, so this
change allows it to use .
The actual contents for flag selection will be included in the next PR.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [x] I have read and accepted the CLA agreement (only required once).

## Please put your Discord username so you can be contacted if a bug or
regression is found:

aotumuri

---------

Co-authored-by: Scott Anderson <662325+scottanderson@users.noreply.github.com>

src/client/components/baseComponents/Modal.ts

@@ -7,6 +7,7 @@ export class OModal extends LitElement {
   @state() public isModalOpen = false;
   @property({ type: String }) title = "";
   @property({ type: String }) translationKey = "";
+  @property({ type: Boolean }) alwaysMaximized = false;
 
   static styles = css`
     .c-modal {
@@ -31,6 +32,17 @@ export class OModal extends LitElement {
       max-width: 860px;
     }
 
+    .c-modal__wrapper.always-maximized {
+      width: 100%;
+      min-width: 340px;
+      max-width: 860px;
+      min-height: 320px;
+      /* Fallback for older browsers */
+      height: 60vh;
+      /* Use dvh if supported for dynamic viewport handling */
+      height: 60dvh;
+    }
+
     .c-modal__header {
       position: relative;
       border-top-left-radius: 4px;
@@ -74,7 +86,11 @@ export class OModal extends LitElement {
       ${this.isModalOpen
         ? html`
             <aside class="c-modal">
-              <div class="c-modal__wrapper">
+              <div
+                class="c-modal__wrapper ${this.alwaysMaximized
+                  ? "always-maximized"
+                  : ""}"
+              >
                 <header class="c-modal__header">
                   ${`${this.translationKey}` === ""
                     ? `${this.title}`