Add AI categorization with Ollama: settings, auto-classify on sync/import, and manual classify from Transactions

Adds local LLM-based transaction categorization using Ollama:
- Settings UI to configure Ollama URL, model, confidence threshold
- Auto-categorization during bank sync and file import
- Manual "Classify Uncategorized" button on Transactions screen that respects active filters
- Payee default category learning loop for classified transactions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/Purrse.Data/Configurations/AiCategorizationSettingsConfiguration.cs

@@ -0,0 +1,23 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+using Purrse.Core.Models;
+
+namespace Purrse.Data.Configurations;
+
+public class AiCategorizationSettingsConfiguration : IEntityTypeConfiguration<AiCategorizationSettings>
+{
+    public void Configure(EntityTypeBuilder<AiCategorizationSettings> builder)
+    {
+        builder.ToTable("ai_categorization_settings");
+        builder.HasKey(s => s.Id);
+        builder.Property(s => s.OllamaUrl).HasMaxLength(500);
+        builder.Property(s => s.ModelName).HasMaxLength(100);
+
+        builder.HasOne(s => s.User)
+            .WithOne(u => u.AiCategorizationSettings)
+            .HasForeignKey<AiCategorizationSettings>(s => s.UserId)
+            .OnDelete(DeleteBehavior.Cascade);
+
+        builder.HasIndex(s => s.UserId).IsUnique();
+    }
+}

src/Purrse.Data/Migrations/20260208232419_AddAiCategorizationSettings.cs

@@ -0,0 +1,53 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Purrse.Data.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddAiCategorizationSettings : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "ai_categorization_settings",
+                columns: table => new
+                {
+                    Id = table.Column<Guid>(type: "uuid", nullable: false),
+                    UserId = table.Column<Guid>(type: "uuid", nullable: false),
+                    IsEnabled = table.Column<bool>(type: "boolean", nullable: false),
+                    OllamaUrl = table.Column<string>(type: "character varying(500)", maxLength: 500, nullable: false),
+                    ModelName = table.Column<string>(type: "character varying(100)", maxLength: 100, nullable: false),
+                    ConfidenceThreshold = table.Column<double>(type: "double precision", nullable: false),
+                    TimeoutSeconds = table.Column<int>(type: "integer", nullable: false),
+                    UpdatePayeeDefaults = table.Column<bool>(type: "boolean", nullable: false),
+                    UpdatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_ai_categorization_settings", x => x.Id);
+                    table.ForeignKey(
+                        name: "FK_ai_categorization_settings_users_UserId",
+                        column: x => x.UserId,
+                        principalTable: "users",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_ai_categorization_settings_UserId",
+                table: "ai_categorization_settings",
+                column: "UserId",
+                unique: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "ai_categorization_settings");
+        }
+    }
+}

src/Purrse.Data/Migrations/PurrseDbContextModelSnapshot.cs

@@ -85,6 +85,48 @@ namespace Purrse.Data.Migrations
                     b.ToTable("accounts", (string)null);
                 });
 
+            modelBuilder.Entity("Purrse.Core.Models.AiCategorizationSettings", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("uuid");
+
+                    b.Property<double>("ConfidenceThreshold")
+                        .HasColumnType("double precision");
+
+                    b.Property<bool>("IsEnabled")
+                        .HasColumnType("boolean");
+
+                    b.Property<string>("ModelName")
+                        .IsRequired()
+                        .HasMaxLength(100)
+                        .HasColumnType("character varying(100)");
+
+                    b.Property<string>("OllamaUrl")
+                        .IsRequired()
+                        .HasMaxLength(500)
+                        .HasColumnType("character varying(500)");
+
+                    b.Property<int>("TimeoutSeconds")
+                        .HasColumnType("integer");
+
+                    b.Property<bool>("UpdatePayeeDefaults")
+                        .HasColumnType("boolean");
+
+                    b.Property<DateTime>("UpdatedAt")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Guid>("UserId")
+                        .HasColumnType("uuid");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("UserId")
+                        .IsUnique();
+
+                    b.ToTable("ai_categorization_settings", (string)null);
+                });
+
             modelBuilder.Entity("Purrse.Core.Models.AmortizationEntry", b =>
                 {
                     b.Property<Guid>("Id")
@@ -994,6 +1036,17 @@ namespace Purrse.Data.Migrations
                     b.Navigation("User");
                 });
 
+            modelBuilder.Entity("Purrse.Core.Models.AiCategorizationSettings", b =>
+                {
+                    b.HasOne("Purrse.Core.Models.User", "User")
+                        .WithOne("AiCategorizationSettings")
+                        .HasForeignKey("Purrse.Core.Models.AiCategorizationSettings", "UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("User");
+                });
+
             modelBuilder.Entity("Purrse.Core.Models.AmortizationEntry", b =>
                 {
                     b.HasOne("Purrse.Core.Models.LoanDetail", "LoanDetail")
@@ -1396,6 +1449,8 @@ namespace Purrse.Data.Migrations
                 {
                     b.Navigation("Accounts");
 
+                    b.Navigation("AiCategorizationSettings");
+
                     b.Navigation("BankSyncSettings");
 
                     b.Navigation("SyncConnections");

src/Purrse.Data/PurrseDbContext.cs

@@ -30,6 +30,7 @@ public class PurrseDbContext : DbContext
     public DbSet<LinkedAccount> LinkedAccounts => Set<LinkedAccount>();
     public DbSet<SyncLog> SyncLogs => Set<SyncLog>();
     public DbSet<BankSyncSettings> BankSyncSettings => Set<BankSyncSettings>();
+    public DbSet<AiCategorizationSettings> AiCategorizationSettings => Set<AiCategorizationSettings>();
 
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {