feat: add CreatedAt to OcrCommand, update Gemini to 2.5-flash

## OcrCommand Enhancement
- Add optional `CreatedAt` parameter for document timestamp tracking
- Fully backward compatible - defaults to null
- New tests for serialization and backward compatibility

## Gemini Model Update
- Update default model from gemini-2.0-flash → gemini-2.5-flash
- Update docs and test fixtures

Bumps to v2.2.0

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: ANcpLua

README.md

@@ -123,7 +123,7 @@ await _publisher.PublishGenAICommandAsync(genAiCommand);
 {
   "Gemini": {
     "ApiKey": "your-api-key",
-    "Model": "gemini-2.0-flash",
+    "Model": "gemini-2.5-flash",
     "TimeoutSeconds": 30
   }
 }

SWEN3.Paperless.RabbitMq.Tests/Unit/GeminiServiceTests.cs

@@ -12,7 +12,7 @@ public class GeminiServiceTests
     private readonly GeminiOptions _options = new()
     {
         ApiKey = "test-key",
-        Model = "gemini-2.0-flash",
+        Model = "gemini-2.5-flash",
         TimeoutSeconds = 5
     };
 

SWEN3.Paperless.RabbitMq.Tests/Unit/GenAIExtensionsTests.cs

@@ -13,7 +13,7 @@ public void AddPaperlessGenAI_RegistersServices()
             .AddInMemoryCollection(new Dictionary<string, string?>
             {
                 ["Gemini:ApiKey"] = "test-key",
-                ["Gemini:Model"] = "gemini-2.0-flash",
+                ["Gemini:Model"] = "gemini-2.5-flash",
                 ["Gemini:TimeoutSeconds"] = "15"
             })
             .Build();
@@ -29,7 +29,7 @@ public void AddPaperlessGenAI_RegistersServices()
 
         var options = provider.GetRequiredService<IOptions<GeminiOptions>>().Value;
         options.ApiKey.Should().Be("test-key");
-        options.Model.Should().Be("gemini-2.0-flash");
+        options.Model.Should().Be("gemini-2.5-flash");
         options.TimeoutSeconds.Should().Be(15);
 
         var summarizer = provider.GetRequiredService<ITextSummarizer>();

SWEN3.Paperless.RabbitMq.Tests/Unit/PublishingExtensionsTests.cs

@@ -14,6 +14,53 @@ public async Task PublishOcrCommandAsync_ShouldPublishWithCorrectRoutingKey()
         _publisherMock.Verify(p => p.PublishAsync(RabbitMqSchema.OcrCommandRouting, command), Times.Once);
     }
 
+    [Fact]
+    public async Task PublishOcrCommandAsync_WithCreatedAt_ShouldPublishWithTimestamp()
+    {
+        var createdAt = DateTimeOffset.UtcNow.AddHours(-1);
+        var command = new OcrCommand(Guid.NewGuid(), "document.pdf", "/path/to/document.pdf", createdAt);
+
+        await _publisherMock.Object.PublishOcrCommandAsync(command);
+
+        _publisherMock.Verify(p => p.PublishAsync(
+            RabbitMqSchema.OcrCommandRouting,
+            It.Is<OcrCommand>(c => c.CreatedAt == createdAt)), Times.Once);
+    }
+
+    [Fact]
+    public void OcrCommand_WithoutCreatedAt_ShouldDefaultToNull()
+    {
+        var command = new OcrCommand(Guid.NewGuid(), "document.pdf", "/path/to/document.pdf");
+
+        command.CreatedAt.Should().BeNull();
+    }
+
+    [Fact]
+    public void OcrCommand_SerializesAndDeserializesCreatedAt()
+    {
+        var createdAt = DateTimeOffset.UtcNow.AddDays(-1);
+        var original = new OcrCommand(Guid.NewGuid(), "test.pdf", "/test.pdf", createdAt);
+
+        var json = JsonSerializer.Serialize(original);
+        var deserialized = JsonSerializer.Deserialize<OcrCommand>(json);
+
+        deserialized.Should().NotBeNull();
+        deserialized!.CreatedAt.Should().BeCloseTo(createdAt, TimeSpan.FromMilliseconds(1));
+    }
+
+    [Fact]
+    public void OcrCommand_DeserializesWithoutCreatedAt_BackwardCompatibility()
+    {
+        // Simulate old JSON without CreatedAt field
+        var json = """{"JobId":"550e8400-e29b-41d4-a716-446655440000","FileName":"old.pdf","FilePath":"/old.pdf"}""";
+
+        var deserialized = JsonSerializer.Deserialize<OcrCommand>(json);
+
+        deserialized.Should().NotBeNull();
+        deserialized!.CreatedAt.Should().BeNull();
+        deserialized.FileName.Should().Be("old.pdf");
+    }
+
     [Fact]
     public async Task PublishOcrEventAsync_ShouldPublishWithCorrectRoutingKey()
     {

SWEN3.Paperless.RabbitMq/GenAI/GeminiOptions.cs

@@ -30,13 +30,13 @@ public sealed class GeminiOptions
     ///     Gets or initializes the Gemini model identifier to use for text generation.
     /// </summary>
     /// <value>
-    ///     The model name. Defaults to "gemini-2.0-flash" for optimal balance of speed and quality.
+    ///     The model name. Defaults to "gemini-2.5-flash" for optimal balance of speed and quality.
     /// </value>
     /// <remarks>
-    ///     Available models include "gemini-2.0-flash", "gemini-1.5-pro", and "gemini-1.5-flash".
+    ///     Available models include "gemini-2.5-flash", "gemini-2.5-pro", and "gemini-2.5-flash-lite".
     ///     See Google AI documentation for current model availability and capabilities.
     /// </remarks>
-    public string Model { get; init; } = "gemini-2.0-flash";
+    public string Model { get; init; } = "gemini-2.5-flash";
 
     /// <summary>
     ///     Gets or initializes the timeout duration in seconds for HTTP client requests.

SWEN3.Paperless.RabbitMq/GenAI/GenAIExtensions.cs

@@ -35,7 +35,7 @@ public static class GenAIExtensions
     ///     {
     ///       "Gemini": {
     ///         "ApiKey": "your-api-key",
-    ///         "Model": "gemini-2.0-flash",
+    ///         "Model": "gemini-2.5-flash",
     ///         "TimeoutSeconds": 30
     ///       }
     ///     }

SWEN3.Paperless.RabbitMq/Models/OcrCommand.cs

@@ -9,5 +9,9 @@ namespace SWEN3.Paperless.RabbitMq.Models;
 /// <param name="JobId">Unique identifier for the OCR job.</param>
 /// <param name="FileName">Name of the file to process.</param>
 /// <param name="FilePath">Path to the file in storage.</param>
+/// <param name="CreatedAt">
+///     When the document was originally uploaded. Optional for backward compatibility.
+///     Consumers should fall back to <see cref="DateTimeOffset.UtcNow" /> if null.
+/// </param>
 /// <seealso cref="OcrEvent" />
-public record OcrCommand(Guid JobId, string FileName, string FilePath);
+public record OcrCommand(Guid JobId, string FileName, string FilePath, DateTimeOffset? CreatedAt = null);

SWEN3.Paperless.RabbitMq/SWEN3.Paperless.RabbitMq.csproj

@@ -8,7 +8,7 @@
 
     <PackageId>SWEN3.Paperless.RabbitMq</PackageId>
     <Title>SWEN3.Paperless.RabbitMq - RabbitMQ Messaging with SSE Streaming &amp; AI Summarization</Title>
-    <Version>2.1.2</Version>
+    <Version>2.2.0</Version>
     <Authors>Alexander Nachtmann</Authors>
     <Copyright>Copyright © 2025 Alexander Nachtmann</Copyright>