fix(profile): the handle's hint says it is private until the profile is public (ADR 0020, D5)

A handle alone is private: its page and `profiles.byHandle` answer as
for a handle nobody has until its person fills in their profile or
publishes something. The hint under it said "Others find you as @…"
all the same, also after removing a profile (D27). It now says it is
private until then, by the rule the instance's `isPublic` applies.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

apps/learn/halkyon_learn_flutter/lib/l10n/app_de.arb

@@ -485,6 +485,8 @@
   "publicProfileHandleHint": "Buchstaben, Ziffern und Unterstriche, bis zu 30",
   "publicProfileAddress": "Andere finden dich als @{address}",
   "@publicProfileAddress": {"placeholders": {"address": {"type": "String"}}},
+  "publicProfileAddressPrivate": "Privat, bis du dein Profil ausfüllst oder etwas veröffentlichst; dann finden dich andere als @{address}.",
+  "@publicProfileAddressPrivate": {"placeholders": {"address": {"type": "String"}}},
   "publicProfileHandleFixed": "Fest, seit du veröffentlicht hast: Andere verweisen darauf.",
   "publicProfileBio": "Über dich",
   "publicProfileLinks": "Links",

apps/learn/halkyon_learn_flutter/lib/l10n/app_en.arb

@@ -550,6 +550,8 @@
   "publicProfileHandleHint": "Letters, digits and underscores, up to 30",
   "publicProfileAddress": "Others find you as @{address}",
   "@publicProfileAddress": {"placeholders": {"address": {"type": "String"}}},
+  "publicProfileAddressPrivate": "Private until you fill in your profile or publish something; then others find you as @{address}.",
+  "@publicProfileAddressPrivate": {"placeholders": {"address": {"type": "String"}}},
   "publicProfileHandleFixed": "Fixed since you published: others refer to it.",
   "publicProfileBio": "Bio",
   "publicProfileLinks": "Links",

apps/learn/halkyon_learn_flutter/lib/l10n/app_localizations.dart

@@ -2914,6 +2914,12 @@ abstract class AppLocalizations {
   /// **'Others find you as @{address}'**
   String publicProfileAddress(String address);
 
+  /// No description provided for @publicProfileAddressPrivate.
+  ///
+  /// In en, this message translates to:
+  /// **'Private until you fill in your profile or publish something; then others find you as @{address}.'**
+  String publicProfileAddressPrivate(String address);
+
   /// No description provided for @publicProfileHandleFixed.
   ///
   /// In en, this message translates to:

apps/learn/halkyon_learn_flutter/lib/l10n/app_localizations_de.dart

@@ -1766,6 +1766,11 @@ class AppLocalizationsDe extends AppLocalizations {
     return 'Andere finden dich als @$address';
   }
 
+  @override
+  String publicProfileAddressPrivate(String address) {
+    return 'Privat, bis du dein Profil ausfüllst oder etwas veröffentlichst; dann finden dich andere als @$address.';
+  }
+
   @override
   String get publicProfileHandleFixed =>
       'Fest, seit du veröffentlicht hast: Andere verweisen darauf.';

apps/learn/halkyon_learn_flutter/lib/l10n/app_localizations_en.dart

@@ -1750,6 +1750,11 @@ class AppLocalizationsEn extends AppLocalizations {
     return 'Others find you as @$address';
   }
 
+  @override
+  String publicProfileAddressPrivate(String address) {
+    return 'Private until you fill in your profile or publish something; then others find you as @$address.';
+  }
+
   @override
   String get publicProfileHandleFixed =>
       'Fixed since you published: others refer to it.';