feat(settings): About section — vendor, versions, license, contact

Procurement personas found no vendor, version, license, or
support information anywhere in the app (a hard checklist fail
for regulated buyers). Settings gains an About category:
product name, Studio + running-hub version, vendor Flemming.AI,
author, Apache 2.0 license, contact address, and the docs URL —
every value selectable and one-click copyable. Studio version
constant moved to data/about_info.dart so sidebar tag and About
can never drift. Bumps Studio to 0.71.0.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/l10n/app_de.arb

@@ -1549,6 +1549,21 @@
   "doctorPathStudioErrors": "Studio-Fehler",
   "settingsCategoryGeneral": "Allgemein",
   "settingsCategoryAppearance": "Darstellung",
+  "settingsCategoryAbout": "Über",
+  "aboutPanelTitle": "Über Ch∆In",
+  "aboutPanelBody": "Produkt-, Hersteller- und Lizenzangaben dieser Installation — alle Werte sind kopierbar.",
+  "aboutProduct": "Produkt",
+  "aboutStudioVersion": "Studio-Version",
+  "aboutHubVersion": "Hub-Version",
+  "aboutHubVersionUnknown": "nicht verbunden",
+  "aboutVendor": "Hersteller",
+  "aboutAuthor": "Autor",
+  "aboutLicense": "Lizenz",
+  "aboutContact": "Kontakt",
+  "aboutDocs": "Dokumentation",
+  "aboutOpenLink": "Im Browser öffnen",
+  "aboutCopyTooltip": "Kopieren",
+  "aboutCopiedToast": "In die Zwischenablage kopiert.",
   "sidebarSearchLabel": "Suchen & Befehle",
   "settingsSidebarPinnedTitle": "Navigation immer ausgeklappt",
   "settingsSidebarPinnedBody": "Zeigt die Beschriftungen der Seitenleiste dauerhaft an, statt sie nur beim Überfahren mit der Maus einzublenden.",

lib/l10n/app_en.arb

@@ -1573,6 +1573,21 @@
   "doctorPathStudioErrors": "Studio errors",
   "settingsCategoryGeneral": "General",
   "settingsCategoryAppearance": "Appearance",
+  "settingsCategoryAbout": "About",
+  "aboutPanelTitle": "About Ch∆In",
+  "aboutPanelBody": "Product, vendor, and license details of this installation — every value is copyable.",
+  "aboutProduct": "Product",
+  "aboutStudioVersion": "Studio version",
+  "aboutHubVersion": "Hub version",
+  "aboutHubVersionUnknown": "not connected",
+  "aboutVendor": "Vendor",
+  "aboutAuthor": "Author",
+  "aboutLicense": "License",
+  "aboutContact": "Contact",
+  "aboutDocs": "Documentation",
+  "aboutOpenLink": "Open in browser",
+  "aboutCopyTooltip": "Copy",
+  "aboutCopiedToast": "Copied to the clipboard.",
   "sidebarSearchLabel": "Search & commands",
   "settingsSidebarPinnedTitle": "Keep the navigation expanded",
   "settingsSidebarPinnedBody": "Shows the sidebar labels permanently instead of only while hovering with the mouse.",

lib/l10n/app_localizations.dart

@@ -4544,6 +4544,96 @@ abstract class AppLocalizations {
   /// **'Appearance'**
   String get settingsCategoryAppearance;
 
+  /// No description provided for @settingsCategoryAbout.
+  ///
+  /// In en, this message translates to:
+  /// **'About'**
+  String get settingsCategoryAbout;
+
+  /// No description provided for @aboutPanelTitle.
+  ///
+  /// In en, this message translates to:
+  /// **'About Ch∆In'**
+  String get aboutPanelTitle;
+
+  /// No description provided for @aboutPanelBody.
+  ///
+  /// In en, this message translates to:
+  /// **'Product, vendor, and license details of this installation — every value is copyable.'**
+  String get aboutPanelBody;
+
+  /// No description provided for @aboutProduct.
+  ///
+  /// In en, this message translates to:
+  /// **'Product'**
+  String get aboutProduct;
+
+  /// No description provided for @aboutStudioVersion.
+  ///
+  /// In en, this message translates to:
+  /// **'Studio version'**
+  String get aboutStudioVersion;
+
+  /// No description provided for @aboutHubVersion.
+  ///
+  /// In en, this message translates to:
+  /// **'Hub version'**
+  String get aboutHubVersion;
+
+  /// No description provided for @aboutHubVersionUnknown.
+  ///
+  /// In en, this message translates to:
+  /// **'not connected'**
+  String get aboutHubVersionUnknown;
+
+  /// No description provided for @aboutVendor.
+  ///
+  /// In en, this message translates to:
+  /// **'Vendor'**
+  String get aboutVendor;
+
+  /// No description provided for @aboutAuthor.
+  ///
+  /// In en, this message translates to:
+  /// **'Author'**
+  String get aboutAuthor;
+
+  /// No description provided for @aboutLicense.
+  ///
+  /// In en, this message translates to:
+  /// **'License'**
+  String get aboutLicense;
+
+  /// No description provided for @aboutContact.
+  ///
+  /// In en, this message translates to:
+  /// **'Contact'**
+  String get aboutContact;
+
+  /// No description provided for @aboutDocs.
+  ///
+  /// In en, this message translates to:
+  /// **'Documentation'**
+  String get aboutDocs;
+
+  /// No description provided for @aboutOpenLink.
+  ///
+  /// In en, this message translates to:
+  /// **'Open in browser'**
+  String get aboutOpenLink;
+
+  /// No description provided for @aboutCopyTooltip.
+  ///
+  /// In en, this message translates to:
+  /// **'Copy'**
+  String get aboutCopyTooltip;
+
+  /// No description provided for @aboutCopiedToast.
+  ///
+  /// In en, this message translates to:
+  /// **'Copied to the clipboard.'**
+  String get aboutCopiedToast;
+
   /// No description provided for @sidebarSearchLabel.
   ///
   /// In en, this message translates to:

lib/l10n/app_localizations_de.dart

@@ -2666,6 +2666,52 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get settingsCategoryAppearance => 'Darstellung';
 
+  @override
+  String get settingsCategoryAbout => 'Über';
+
+  @override
+  String get aboutPanelTitle => 'Über Ch∆In';
+
+  @override
+  String get aboutPanelBody =>
+      'Produkt-, Hersteller- und Lizenzangaben dieser Installation — alle Werte sind kopierbar.';
+
+  @override
+  String get aboutProduct => 'Produkt';
+
+  @override
+  String get aboutStudioVersion => 'Studio-Version';
+
+  @override
+  String get aboutHubVersion => 'Hub-Version';
+
+  @override
+  String get aboutHubVersionUnknown => 'nicht verbunden';
+
+  @override
+  String get aboutVendor => 'Hersteller';
+
+  @override
+  String get aboutAuthor => 'Autor';
+
+  @override
+  String get aboutLicense => 'Lizenz';
+
+  @override
+  String get aboutContact => 'Kontakt';
+
+  @override
+  String get aboutDocs => 'Dokumentation';
+
+  @override
+  String get aboutOpenLink => 'Im Browser öffnen';
+
+  @override
+  String get aboutCopyTooltip => 'Kopieren';
+
+  @override
+  String get aboutCopiedToast => 'In die Zwischenablage kopiert.';
+
   @override
   String get sidebarSearchLabel => 'Suchen & Befehle';
 

lib/l10n/app_localizations_en.dart

@@ -2668,6 +2668,52 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get settingsCategoryAppearance => 'Appearance';
 
+  @override
+  String get settingsCategoryAbout => 'About';
+
+  @override
+  String get aboutPanelTitle => 'About Ch∆In';
+
+  @override
+  String get aboutPanelBody =>
+      'Product, vendor, and license details of this installation — every value is copyable.';
+
+  @override
+  String get aboutProduct => 'Product';
+
+  @override
+  String get aboutStudioVersion => 'Studio version';
+
+  @override
+  String get aboutHubVersion => 'Hub version';
+
+  @override
+  String get aboutHubVersionUnknown => 'not connected';
+
+  @override
+  String get aboutVendor => 'Vendor';
+
+  @override
+  String get aboutAuthor => 'Author';
+
+  @override
+  String get aboutLicense => 'License';
+
+  @override
+  String get aboutContact => 'Contact';
+
+  @override
+  String get aboutDocs => 'Documentation';
+
+  @override
+  String get aboutOpenLink => 'Open in browser';
+
+  @override
+  String get aboutCopyTooltip => 'Copy';
+
+  @override
+  String get aboutCopiedToast => 'Copied to the clipboard.';
+
   @override
   String get sidebarSearchLabel => 'Search & commands';