feat: enrich Settings → App Info with metadata & resource links (#56)

Replaces the three-row App Info screen with a full About/Resources/Support/
Legal layout, driven by a declarative AppInfoRow model with all URLs centralized
in one AppLinks namespace.

- About: Version now shows "5.0.0 (build N)" (CFBundleShortVersionString +
  CFBundleVersion), plus Storage, Backup Schema, and Minimum iOS (17.6).
- Resources: What's New (bundled ReleaseNotes.json sheet, no network),
  Documentation & FAQ, Source Code, Privacy Policy, and Acknowledgements
  ("no third-party dependencies" + MIT license).
- Support: Report an Issue (a sheet that shows the locally-assembled
  version/OS/device diagnostics before offering Email or GitHub — nothing is
  collected silently) and Contact (mailto).
- Support the App: Rate (SwiftUI's @Environment(\.requestReview), which handles
  the scene internally and respects Apple's throttling — the modern, safer
  equivalent of the issue's SKStoreReviewController + connectedScenes path) and
  Share (ShareLink to the App Store listing).
- Legal: copyright footer with the current year.

External rows use Link/openURL with an "opens outside the app" accessibility
hint; the screen is standard adaptive Form controls with semantic colors, so it
tracks Dynamic Type and light/dark automatically.

New files (AppLinks, AppInfo, ReleaseNotes[.swift/.json], AppInfoView) auto-
compile/bundle via the synchronized DomainDig/ group. AppInfoTests covers the
mailto builder, version format, diagnostics contents, and that the bundled notes
ship and parse. Unit suite green.

Placeholder pending the App Store listing: AppLinks.appStoreID (the review/share
URLs derive from it), flagged with a TODO.

1 files changed, 34 insertions, 0 deletions

diff --git a/DomainDig/AppLinks.swift b/DomainDig/AppLinks.swift
new file mode 100644
index 0000000..39c9036
--- /dev/null
+++ b/DomainDig/AppLinks.swift
@@ -0,0 +1,34 @@
+import Foundation
+
+/// Centralized external destinations, kept in one place so URLs and the App Store
+/// identifier can be swapped without touching any view.
+///
+/// TODO(release): `appStoreID` is a placeholder until the App Store listing is
+/// live — the listing/review/share URLs derive from it. `documentation` points
+/// at the repository README for now; swap in a dedicated docs site if one lands.
+enum AppLinks {
+    /// App Store numeric identifier. Placeholder until the listing is published.
+    static let appStoreID = "0000000000"
+
+    static let sourceCode = url("https://github.com/zerolabsco/domain-dig")
+    static let documentation = url("https://github.com/zerolabsco/domain-dig#readme")
+    static let privacyPolicy = url("https://zerolabs.sh/domaindig/privacy-policy/")
+    static let supportEmail = "[email protected]"
+
+    static var appStoreListing: URL { url("https://apps.apple.com/app/id\(appStoreID)") }
+    static var writeReview: URL { url("https://apps.apple.com/app/id\(appStoreID)?action=write-review") }
+
+    static var copyright: String {
+        let year = Calendar.current.component(.year, from: Date())
+        return "© \(year) Christian Cleberg"
+    }
+
+    /// Builds URLs from developer-controlled literals; a malformed literal is a
+    /// programming error, surfaced loudly in development rather than force-unwrapped.
+    private static func url(_ string: String) -> URL {
+        guard let url = URL(string: string) else {
+            preconditionFailure("Invalid AppLinks URL literal: \(string)")
+        }
+        return url
+    }
+}