858/03: peel Agent into AgentDbContext

.github/workflows/build.yml

@@ -44,7 +44,7 @@ jobs:
       # context since the per-section split (nobodies-collective/Humans#858).
       run: |
         dotnet tool install --global dotnet-ef --version 10.0.*
-        for ctx in HumansDbContext SystemSettingsDbContext ContainersDbContext; do
+        for ctx in HumansDbContext SystemSettingsDbContext ContainersDbContext AgentDbContext; do
           dotnet ef migrations has-pending-model-changes \
             --context "$ctx" \
             --project src/Humans.Infrastructure \
@@ -174,7 +174,7 @@ jobs:
       - name: Apply per-section baselines from scratch
         run: |
           set -euo pipefail
-          for ctx in SystemSettingsDbContext ContainersDbContext; do
+          for ctx in SystemSettingsDbContext ContainersDbContext AgentDbContext; do
             db="humans_$(echo "$ctx" | tr '[:upper:]' '[:lower:]')"
             docker exec "${{ steps.pg.outputs.container }}" \
               psql -U humans -d postgres -c "CREATE DATABASE $db"
@@ -193,7 +193,7 @@ jobs:
           # Belt-and-suspenders: Layer 1 already runs this in the build job,
           # but re-checking after a real apply guards against any state the
           # apply step might have observed differently from a static check.
-          for ctx in HumansDbContext SystemSettingsDbContext ContainersDbContext; do
+          for ctx in HumansDbContext SystemSettingsDbContext ContainersDbContext AgentDbContext; do
             dotnet ef migrations has-pending-model-changes \
               --context "$ctx" \
               --project src/Humans.Infrastructure \

src/Humans.Infrastructure/Data/AgentDbContext.cs

@@ -0,0 +1,35 @@
+using Humans.Domain.Entities;
+using Humans.Infrastructure.Data.Configurations.Agent;
+using Microsoft.EntityFrameworkCore;
+
+namespace Humans.Infrastructure.Data;
+
+/// <summary>
+/// Per-section database context for the Agent section
+/// (nobodies-collective/Humans#858): maps only <c>agent_conversations</c>,
+/// <c>agent_messages</c> and <c>agent_settings</c>, with its own
+/// <c>__EFMigrationsHistory_Agent</c> table and migrations under
+/// <c>Migrations/Agent/</c>. Same database, same connection — the split
+/// is a code-side partition of the EF model.
+/// </summary>
+/// <remarks>
+/// Internal-sealed like <see cref="HumansDbContext"/> (issue #750): repositories
+/// are the only consumers. Configurations are applied explicitly (not by
+/// assembly scanning) so this model can never accrete another section's tables.
+/// </remarks>
+internal sealed class AgentDbContext(DbContextOptions<AgentDbContext> options)
+    : DbContext(options)
+{
+    public DbSet<AgentConversation> AgentConversations => Set<AgentConversation>();
+    public DbSet<AgentMessage> AgentMessages => Set<AgentMessage>();
+    public DbSet<AgentSettings> AgentSettings => Set<AgentSettings>();
+
+    protected override void OnModelCreating(ModelBuilder builder)
+    {
+        base.OnModelCreating(builder);
+
+        builder.ApplyConfiguration(new AgentConversationConfiguration());
+        builder.ApplyConfiguration(new AgentMessageConfiguration());
+        builder.ApplyConfiguration(new AgentSettingsConfiguration());
+    }
+}

src/Humans.Infrastructure/Data/AgentDbContextFactory.cs

@@ -0,0 +1,33 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Design;
+
+namespace Humans.Infrastructure.Data;
+
+/// <summary>
+/// Design-time factory used by <c>dotnet ef … --context AgentDbContext</c>.
+/// Mirrors <see cref="HumansDbContextFactory"/>; the migrations-history table must
+/// match the runtime registration so CI's from-scratch apply records baselines in
+/// <c>__EFMigrationsHistory_Agent</c>.
+/// </summary>
+internal sealed class AgentDbContextFactory : IDesignTimeDbContextFactory<AgentDbContext>
+{
+    public AgentDbContext CreateDbContext(string[] args)
+    {
+        var connectionString =
+            Environment.GetEnvironmentVariable("ConnectionStrings__DefaultConnection")
+            ?? "Host=localhost;Database=humans_design_time;Username=humans;Password=humans";
+
+        var optionsBuilder = new DbContextOptionsBuilder<AgentDbContext>();
+        optionsBuilder.UseNpgsql(
+            connectionString,
+            npgsqlOptions =>
+            {
+                npgsqlOptions.UseNodaTime();
+                npgsqlOptions.MigrationsAssembly("Humans.Infrastructure");
+                npgsqlOptions.MigrationsHistoryTable("__EFMigrationsHistory_Agent");
+                npgsqlOptions.UseQuerySplittingBehavior(QuerySplittingBehavior.SplitQuery);
+            });
+
+        return new AgentDbContext(optionsBuilder.Options);
+    }
+}

src/Humans.Infrastructure/Data/Configurations/AgentConversationConfiguration.cs → src/Humans.Infrastructure/Data/Configurations/Agent/AgentConversationConfiguration.cs

@@ -2,7 +2,7 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 
-namespace Humans.Infrastructure.Data.Configurations;
+namespace Humans.Infrastructure.Data.Configurations.Agent;
 
 public class AgentConversationConfiguration : IEntityTypeConfiguration<AgentConversation>
 {

src/Humans.Infrastructure/Data/Configurations/AgentMessageConfiguration.cs → src/Humans.Infrastructure/Data/Configurations/Agent/AgentMessageConfiguration.cs

@@ -3,7 +3,7 @@
 using Microsoft.EntityFrameworkCore.ChangeTracking;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 
-namespace Humans.Infrastructure.Data.Configurations;
+namespace Humans.Infrastructure.Data.Configurations.Agent;
 
 public class AgentMessageConfiguration : IEntityTypeConfiguration<AgentMessage>
 {

src/Humans.Infrastructure/Data/Configurations/AgentSettingsConfiguration.cs → src/Humans.Infrastructure/Data/Configurations/Agent/AgentSettingsConfiguration.cs

@@ -4,7 +4,7 @@
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 using NodaTime;
 
-namespace Humans.Infrastructure.Data.Configurations;
+namespace Humans.Infrastructure.Data.Configurations.Agent;
 
 public class AgentSettingsConfiguration : IEntityTypeConfiguration<AgentSettings>
 {

src/Humans.Infrastructure/Data/HumansDbContext.cs

@@ -84,9 +84,6 @@ internal sealed class HumansDbContext(DbContextOptions<HumansDbContext> options)
     public DbSet<FeedbackMessage> FeedbackMessages => Set<FeedbackMessage>();
     public DbSet<Issue> Issues => Set<Issue>();
     public DbSet<IssueComment> IssueComments => Set<IssueComment>();
-    public DbSet<AgentConversation> AgentConversations => Set<AgentConversation>();
-    public DbSet<AgentMessage> AgentMessages => Set<AgentMessage>();
-    public DbSet<AgentSettings> AgentSettings => Set<AgentSettings>();
     public DbSet<AccountMergeRequest> AccountMergeRequests => Set<AccountMergeRequest>();
     public DbSet<CommunicationPreference> CommunicationPreferences => Set<CommunicationPreference>();
     public DbSet<BudgetYear> BudgetYears => Set<BudgetYear>();
@@ -139,6 +136,7 @@ public DbSet<HoldedExpenseOutboxEvent> HoldedExpenseOutboxEvents
     [
         typeof(Configurations.SystemSettings.SystemSettingConfiguration).Namespace!,
         typeof(Configurations.Containers.ContainerConfiguration).Namespace!,
+        typeof(Configurations.Agent.AgentConversationConfiguration).Namespace!,
     ];
 
     protected override void OnModelCreating(ModelBuilder builder)

src/Humans.Infrastructure/Hosting/InfrastructureServiceCollectionExtensions.cs

@@ -48,6 +48,7 @@ public static IServiceCollection AddHumansPersistence(
         // HumansDbContext by DatabaseMigrationHostedService in registration order.
         services.AddSectionDbContext<SystemSettingsDbContext>(sentinelTable: "system_settings");
         services.AddSectionDbContext<ContainersDbContext>(sentinelTable: "containers");
+        services.AddSectionDbContext<AgentDbContext>(sentinelTable: "agent_conversations");
 
         services.AddHostedService<DatabaseMigrationHostedService>();