feat: Prompt to manually link unmatched platforms in match-platforms

After automatic matching, interactively let the operator search the
local platform catalog, create a new platform, skip, or quit ('q')
for any platform that couldn't be matched automatically. Skipped
entirely when stdin is redirected to avoid hanging non-interactive runs.

Marechai.Igdb/Services/PlatformMatcher.cs

@@ -38,6 +38,8 @@ public class PlatformMatcher
         int matched     = 0;
         int needsReview = 0;
 
+        var unresolved = new List<IgdbPlatform>();
+
         foreach(IgdbPlatform igdbPlatform in pending)
         {
             string normalizedInput = Normalize(igdbPlatform.Name);
@@ -105,15 +107,144 @@ public class PlatformMatcher
             if(match != null)
                 matched++;
             else
+            {
                 needsReview++;
+                unresolved.Add(igdbPlatform);
+            }
         }
 
         if(!dryRun)
             await context.SaveChangesAsync();
 
+        if(!dryRun && unresolved.Count > 0)
+        {
+            if(Console.IsInputRedirected)
+                Console.WriteLine(
+                    $"\n{unresolved.Count} platform(s) could not be automatically matched. Run interactively (not redirected) to link them manually.");
+            else
+                (matched, needsReview) = await ResolveInteractivelyAsync(context, platforms, unresolved, matched,
+                                                                            needsReview);
+        }
+
         return (matched, needsReview);
     }
 
+    /// <summary>Walks the platforms that automatic matching could not resolve, one at a time, letting the
+    /// operator search the existing local catalog, create a brand-new <see cref="SoftwarePlatform" />, skip the
+    /// current one, or quit (leaving any remaining platforms as <see cref="IgdbMatchStatus.NeedsReview" /> for a
+    /// later run).</summary>
+    async Task<(int matched, int needsReview)> ResolveInteractivelyAsync(MarechaiContext context,
+        List<SoftwarePlatform> platforms, List<IgdbPlatform> unresolved, int matched, int needsReview)
+    {
+        Console.WriteLine(
+            $"\n{unresolved.Count} platform(s) could not be automatically matched. Resolve them now, or press 'q' at any prompt to stop and leave the rest unresolved.");
+
+        foreach(IgdbPlatform igdbPlatform in unresolved)
+        {
+            (SoftwarePlatform resolved, bool quit) = PromptForPlatform(igdbPlatform, platforms);
+
+            if(quit)
+            {
+                Console.WriteLine("  Quitting; remaining platforms left as \"needs review\".");
+
+                break;
+            }
+
+            if(resolved == null)
+                continue;
+
+            if(resolved.Id == 0)
+            {
+                context.SoftwarePlatforms.Add(resolved);
+                await context.SaveChangesAsync();
+                platforms.Add(resolved);
+                Console.WriteLine($"  Created new platform \"{resolved.Name}\" (id {resolved.Id}).");
+            }
+
+            igdbPlatform.SoftwarePlatformId = resolved.Id;
+            igdbPlatform.MatchStatus        = IgdbMatchStatus.Matched;
+            igdbPlatform.MatchType          = "manual";
+            igdbPlatform.MatchedOn          = DateTime.UtcNow;
+
+            matched++;
+            needsReview--;
+
+            await context.SaveChangesAsync();
+            Console.WriteLine($"  Linked \"{igdbPlatform.Name}\" to \"{resolved.Name}\" (id {resolved.Id}).");
+        }
+
+        return (matched, needsReview);
+    }
+
+    /// <summary>Prompts for a single platform. Returns <c>(null, true)</c> on quit, <c>(null, false)</c> on
+    /// skip, or the chosen/newly-built <see cref="SoftwarePlatform" /> (unsaved if newly built, signaled by
+    /// <see cref="SoftwarePlatform.Id" /> being <c>0</c>) otherwise.</summary>
+    static (SoftwarePlatform platform, bool quit) PromptForPlatform(IgdbPlatform igdbPlatform,
+        List<SoftwarePlatform> platforms)
+    {
+        while(true)
+        {
+            Console.WriteLine();
+            Console.WriteLine($"Unmatched IGDB platform: \"{igdbPlatform.Name}\" (igdb id {igdbPlatform.Id}).");
+            Console.Write(
+                "  Enter part of the local platform name to search, 'n' to create a new platform with this name, 's' to skip, or 'q' to quit: ");
+
+            string input = Console.ReadLine()?.Trim();
+
+            if(input == null)
+                return (null, true);
+
+            if(input.Length == 0)
+                continue;
+
+            if(input.Equals("q", StringComparison.OrdinalIgnoreCase))
+                return (null, true);
+
+            if(input.Equals("s", StringComparison.OrdinalIgnoreCase))
+                return (null, false);
+
+            if(input.Equals("n", StringComparison.OrdinalIgnoreCase))
+            {
+                Console.Write($"  Create new platform named \"{igdbPlatform.Name}\"? [Y/n/q]: ");
+                string confirm = Console.ReadLine()?.Trim();
+
+                if(confirm != null && confirm.Equals("q", StringComparison.OrdinalIgnoreCase))
+                    return (null, true);
+
+                if(confirm == null || confirm.Length == 0 || confirm.Equals("y", StringComparison.OrdinalIgnoreCase))
+                    return (new SoftwarePlatform { Name = igdbPlatform.Name }, false);
+
+                continue;
+            }
+
+            List<SoftwarePlatform> candidates = platforms
+                                                .Where(p => p.Name.Contains(input, StringComparison.OrdinalIgnoreCase))
+                                                .OrderBy(p => p.Name).ToList();
+
+            if(candidates.Count == 0)
+            {
+                Console.WriteLine("  No local platforms match that text. Try again.");
+
+                continue;
+            }
+
+            for(int i = 0; i < candidates.Count; i++)
+                Console.WriteLine($"  [{i + 1}] {candidates[i].Name}");
+
+            Console.Write($"  Pick a number (1-{candidates.Count}), 'q' to quit, or anything else to search again: ");
+            string choice = Console.ReadLine()?.Trim();
+
+            if(choice == null)
+                return (null, true);
+
+            if(choice.Equals("q", StringComparison.OrdinalIgnoreCase))
+                return (null, true);
+
+            if(int.TryParse(choice, out int idx) && idx >= 1 && idx <= candidates.Count)
+                return (candidates[idx - 1], false);
+        }
+    }
+
     static List<string> Variants(SoftwarePlatform platform)
     {
         var variants = new List<string> { platform.Name };