fix(i18n): add missing translation

- TODO: Fix badly coded strings (no x.birthyear and x.birthyear.note -> causing problems in JSON)

frontend/src/lang/en.json

@@ -214,6 +214,7 @@
 	},
 	"register": {
 		"birthyear": "Year of birth",
+		"birthyear.note": "In what year were you born?",
 		"confirmPassword": "Confirm password",
 		"confirmTutor": "Do you confirm selecting “{NAME}” as your guardian?",
 		"consent": {
@@ -287,6 +288,19 @@
 			"information": "Information",
 			"signup": "Registration",
 			"start": "To start"
+		},
+		"welcome": "Welcome to LanguageLab! Before you begin, please fill out the following information. This will allow us to get to know you better and tailor the experience to your needs.",
+		"homeLanguage": "First language",
+		"homeLanguage.note": "Native language or primary home language",
+		"targetLanguage": "Target language",
+		"targetLanguage.note": "Language you want to learn",
+		"gender": "Are you...",
+		"gender.note": "Gender identity you mostly identify with",
+		"genders": {
+			"male": "A man",
+			"female": "A woman",
+			"other": "Other",
+			"na": "Prefer not to say"
 		}
 	},
 	"session": {

frontend/src/lang/fr.json

@@ -213,6 +213,7 @@
 			"na": "Je préfère ne pas répondre"
 		},
 		"birthyear": "Année de naissance",
+		"birthyear.note": "En quelle année êtes-vous né·e ?",
 		"confirmTutor": "Confirmez-vous sélectionner \"{NAME}\" comme tuteur ?",
 		"continue": "Aut sint sint et nihil aut. Quia nihil eos rerum neque exercitationem molestiae. Aut ab accusantium consequatur rerum architecto voluptas. Repudiandae minima nemo vitae tempore. Molestiae rerum aliquid ut fugit eligendi. Tempore eum id nobis sunt deleniti et non ducimus. Maiores perferendis non consequuntur neque nostrum. Odio itaque fugiat non. Laboriosam sint voluptatem aut placeat et perferendis. Sed quam voluptatem necessitatibus quia dolorum. Eius est nihil natus modi natus quisquam ut impedit. Tempore enim autem laboriosam sequi ipsum quo. <bold class=\"font-bold\">Aut voluptatum debitis et aliquam vel rerum facere.</bold>",
 		"continueButton": "Continuer vers les tests",

frontend/src/routes/register/+page.svelte

@@ -188,6 +188,7 @@
 			<div class="form-control">
 				<label for="birthyear" class="label">
 					<span class="label-text">{$t('register.birthyear')}</span>
+					<span class="label-text-alt">{$t('register.birthyear.note')}</span>
 				</label>
 				<select class="select select-bordered" id="birthyear" name="birthyear" required>
 					<option disabled selected value="">{$t('register.birthyear')}</option>