Fixed bad translation string bug for unit info modal. (#1143)

## Description:
Just cleaning up a small oops I let slip through. 

## 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 understand that submitting code with bugs that could have been
caught through manual testing blocks releases and new features for all
contributors


![image](https://github.com/user-attachments/assets/0ba4855c-5cdc-4a60-be7a-19d1651f573b)

![image](https://github.com/user-attachments/assets/8a1722b3-e44c-4927-bf90-107ecc0c155e)

![image](https://github.com/user-attachments/assets/bca33461-8913-40db-b641-d94b452999d6)

![image](https://github.com/user-attachments/assets/34e9d3f1-e886-4753-beb7-91a8e1ade65a)

![image](https://github.com/user-attachments/assets/4e3ca80a-dcdb-49ea-9742-2c0d93195ea8)

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

src/client/graphics/layers/UnitInfoModal.ts

@@ -79,6 +79,12 @@ export class UnitInfoModal extends LitElement implements Layer {
     super.disconnectedCallback();
   }
 
+  private buildUnitTypeTranslationString(): string {
+    if (!this.unit) return "unit_type.unknown"; // fallback stays the same
+    const unitType = this.unit.type().toLowerCase().replace(/\s+/g, "_");
+    return `unit_type.${unitType}`;
+  }
+
   static styles = css`
     :host {
       position: fixed;
@@ -176,7 +182,7 @@ export class UnitInfoModal extends LitElement implements Layer {
         </div>
         <div style="margin-bottom: 4px;">
           <strong>${translateText("unit_info_modal.type")}:</strong>
-          ${translateText(+"unit_type." + this.unit.type?.().toLowerCase()) ??
+          ${translateText(this.buildUnitTypeTranslationString()) ??
           translateText("unit_info_modal.unit_type_unknown")}
           <strong
             style="display: ${this.game.unitInfo(this.unit.type()).upgradable