Add the Tazel plugin catalog of ViGet to the API

ViGet opens in stages: first only Progmasoft publishes Tazel plugins, later
every account. This adds the catalog and the server-side publishing for the
first stage; nothing publishes through the API yet.

- ViGet/: the catalog of Tazel plugins (in memory, or in PostgreSQL beside
  the accounts with its own numbered schema steps), the descriptor read from
  the JAR (META-INF/tazel-plugin.properties, with a reader of the Java
  properties format, and the ProjectPlugin service entry), and publishing:
  the publisher must be in ViGet:TazelPublishers (Progmasoft for now) and an
  existing account of that exact name, a version is never replaced, names
  that differ only in letter case are refused, and ViGet needs a
  description, an author and a license. The JAR is kept at
  dslplugins/tazel/<Publisher>/<Name>/<Version>/<Name>-<Version>.jar below
  ViGet:ArtifactRoot.
- Read endpoints under /api/v1/viget/dslplugins/tazel: the list, a plugin,
  and index.json, the index Tazel reads.
- 'viget publish-tazel-plugin <jar>' and 'viget yank-tazel-plugin' run with
  the configuration of the service instead of the service.
- The account store can find an account by name.

The pages, the Nginx routes and the deployment follow.

1 files changed, 85 insertions, 0 deletions

diff --git a/apps/api/ViGet/ViGetCommand.cs b/apps/api/ViGet/ViGetCommand.cs
new file mode 100644
index 0000000..ad99aee
--- /dev/null
+++ b/apps/api/ViGet/ViGetCommand.cs
@@ -0,0 +1,85 @@
+// SPDX-FileCopyrightText: 2026 Progmasoft <support@progmasoft.com>
+// SPDX-License-Identifier: AGPL-3.0-or-later WITH AdditionRef-Progmasoft-Patent-Grant-1.1
+
+using Npgsql;
+
+namespace Progmasoft.Progmaweb.Api.ViGet;
+
+/// <summary>
+/// The commands that manage the Tazel plugin catalog on the server, while publishing is not open through the API:
+/// <c>viget publish-tazel-plugin &lt;jar&gt;</c> and <c>viget yank-tazel-plugin &lt;Publisher&gt; &lt;Name&gt;
+/// &lt;Version&gt; [--undo]</c>. They run with the configuration of the service, as its user.
+/// </summary>
+internal static class ViGetCommand
+{
+    /// <summary>Whether the arguments of the program ask for a ViGet command rather than the web service.</summary>
+    public static bool IsCommand(string[] args) => args is ["viget", ..];
+
+    /// <summary>Runs a ViGet command.</summary>
+    /// <param name="services">The services of the API, not started.</param>
+    /// <param name="args">The arguments after <c>viget</c>.</param>
+    /// <param name="output">Where results go.</param>
+    /// <param name="errors">Where errors go.</param>
+    /// <param name="cancellationToken">Cancels the command.</param>
+    /// <returns>The exit code: 0 on success, 1 when the command was refused, 2 for a wrong command line.</returns>
+    public static async Task<int> RunAsync(
+        IServiceProvider services,
+        string[] args,
+        TextWriter output,
+        TextWriter errors,
+        CancellationToken cancellationToken)
+    {
+        // The service applies the schema when it starts; a command may run before it ever did.
+        if (services.GetService<NpgsqlDataSource>() is { } dataSource)
+        {
+            await ViGetSchema.ApplyAsync(dataSource, cancellationToken);
+        }
+
+        switch (args)
+        {
+            case ["publish-tazel-plugin", string path]:
+            {
+                if (!File.Exists(path))
+                {
+                    await errors.WriteLineAsync($"{path} does not exist.");
+                    return 1;
+                }
+
+                TazelPluginPublishing publishing = services.GetRequiredService<TazelPluginPublishing>();
+                PublishResult result = await publishing.PublishAsync(
+                    await File.ReadAllBytesAsync(path, cancellationToken), cancellationToken);
+                if (!result.Published)
+                {
+                    await errors.WriteLineAsync(result.Error);
+                    return 1;
+                }
+
+                TazelPluginDescriptor plugin = result.Plugin!;
+                await output.WriteLineAsync(
+                    $"Published {plugin.Publisher}.{plugin.Name} {plugin.Version}: " +
+                    $"https://viget.progmasoft.com/dslplugins/tazel/{plugin.Publisher}/{plugin.Name}");
+                return 0;
+            }
+            case ["yank-tazel-plugin", string publisher, string name, string version, .. var rest]
+                when rest is [] or ["--undo"]:
+            {
+                bool yanked = rest is [];
+                ITazelPluginCatalog catalog = services.GetRequiredService<ITazelPluginCatalog>();
+                if (!await catalog.SetYankedAsync(publisher, name, version, yanked, cancellationToken))
+                {
+                    await errors.WriteLineAsync($"{publisher}.{name} has no version {version}.");
+                    return 1;
+                }
+
+                await output.WriteLineAsync(
+                    $"{publisher}.{name} {version} is {(yanked ? "yanked" : "no longer yanked")}.");
+                return 0;
+            }
+            default:
+                await errors.WriteLineAsync(
+                    "usage: viget publish-tazel-plugin <jar>\n" +
+                    "       viget yank-tazel-plugin <Publisher> <Name> <Version> [--undo]");
+                return 2;
+        }
+    }
+}