sln build fix (again), tests fixes, audit work and doctors work

src/__Libraries/StellaOps.Doctor.Plugins.Database/Checks/DatabaseCheckBase.cs

@@ -0,0 +1,125 @@
+using Microsoft.Extensions.Configuration;
+using Npgsql;
+using StellaOps.Doctor.Models;
+using StellaOps.Doctor.Plugins;
+
+namespace StellaOps.Doctor.Plugins.Database.Checks;
+
+/// <summary>
+/// Base class for database checks providing common functionality.
+/// </summary>
+public abstract class DatabaseCheckBase : IDoctorCheck
+{
+    private const string DefaultConnectionStringKey = "ConnectionStrings:DefaultConnection";
+    private const string PluginId = "stellaops.doctor.database";
+    private const string CategoryName = "Database";
+
+    /// <inheritdoc />
+    public abstract string CheckId { get; }
+
+    /// <inheritdoc />
+    public abstract string Name { get; }
+
+    /// <inheritdoc />
+    public abstract string Description { get; }
+
+    /// <inheritdoc />
+    public virtual DoctorSeverity DefaultSeverity => DoctorSeverity.Fail;
+
+    /// <inheritdoc />
+    public abstract IReadOnlyList<string> Tags { get; }
+
+    /// <inheritdoc />
+    public virtual TimeSpan EstimatedDuration => TimeSpan.FromSeconds(2);
+
+    /// <inheritdoc />
+    public virtual bool CanRun(DoctorPluginContext context)
+    {
+        var connectionString = GetConnectionString(context);
+        return !string.IsNullOrEmpty(connectionString);
+    }
+
+    /// <inheritdoc />
+    public async Task<DoctorCheckResult> RunAsync(DoctorPluginContext context, CancellationToken ct)
+    {
+        var result = context.CreateResult(CheckId, PluginId, CategoryName);
+
+        var connectionString = GetConnectionString(context);
+        if (string.IsNullOrEmpty(connectionString))
+        {
+            return result
+                .Skip("No database connection string configured")
+                .WithEvidence("Configuration", e => e
+                    .Add("ConnectionStringKey", DefaultConnectionStringKey)
+                    .Add("Configured", "false"))
+                .Build();
+        }
+
+        try
+        {
+            return await ExecuteCheckAsync(context, connectionString, result, ct);
+        }
+        catch (NpgsqlException ex)
+        {
+            return result
+                .Fail($"Database error: {ex.Message}")
+                .WithEvidence("Error details", e => e
+                    .Add("ExceptionType", ex.GetType().Name)
+                    .Add("SqlState", ex.SqlState ?? "(none)")
+                    .Add("Message", ex.Message))
+                .WithCauses(
+                    "Database server unavailable",
+                    "Authentication failed",
+                    "Network connectivity issue")
+                .WithRemediation(r => r
+                    .AddShellStep(1, "Test connection", "psql -h <host> -U <user> -d <database> -c 'SELECT 1'")
+                    .AddManualStep(2, "Check credentials", "Verify database username and password in configuration"))
+                .WithVerification($"stella doctor --check {CheckId}")
+                .Build();
+        }
+        catch (Exception ex)
+        {
+            return result
+                .Fail($"Unexpected error: {ex.Message}")
+                .WithEvidence("Error details", e => e
+                    .Add("ExceptionType", ex.GetType().Name)
+                    .Add("Message", ex.Message))
+                .Build();
+        }
+    }
+
+    /// <summary>
+    /// Executes the specific check logic.
+    /// </summary>
+    protected abstract Task<DoctorCheckResult> ExecuteCheckAsync(
+        DoctorPluginContext context,
+        string connectionString,
+        Builders.CheckResultBuilder result,
+        CancellationToken ct);
+
+    /// <summary>
+    /// Gets the database connection string from configuration.
+    /// </summary>
+    protected static string? GetConnectionString(DoctorPluginContext context)
+    {
+        // Try plugin-specific connection string first
+        var pluginConnectionString = context.PluginConfig["ConnectionString"];
+        if (!string.IsNullOrEmpty(pluginConnectionString))
+        {
+            return pluginConnectionString;
+        }
+
+        // Fall back to default connection string
+        return context.Configuration[DefaultConnectionStringKey];
+    }
+
+    /// <summary>
+    /// Creates a new database connection.
+    /// </summary>
+    protected static async Task<NpgsqlConnection> CreateConnectionAsync(string connectionString, CancellationToken ct)
+    {
+        var connection = new NpgsqlConnection(connectionString);
+        await connection.OpenAsync(ct);
+        return connection;
+    }
+}