Add dummy LLM provider, update Concelier sources and JobEngine endpoints

- AdvisoryAI: DummyLlmProvider for offline/testing scenarios,
  wire in LlmProviderFactory
- Concelier: source definitions, registry, and management endpoint updates
- JobEngine: approval and release endpoint updates
- etc/llm-providers/dummy.yaml config

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/Concelier/StellaOps.Concelier.WebService/Extensions/SourceManagementEndpointExtensions.cs

@@ -1,6 +1,7 @@
 using HttpResults = Microsoft.AspNetCore.Http.Results;
 using Microsoft.AspNetCore.Mvc;
 using StellaOps.Auth.ServerIntegration.Tenancy;
+using StellaOps.Concelier.Core.Jobs;
 using StellaOps.Concelier.Core.Sources;
 
 namespace StellaOps.Concelier.WebService.Extensions;
@@ -220,6 +221,69 @@ internal static class SourceManagementEndpointExtensions
         .Produces(StatusCodes.Status400BadRequest)
         .RequireAuthorization(SourcesManagePolicy);
 
+        // POST /{sourceId}/sync — trigger data sync for a single source
+        group.MapPost("/{sourceId}/sync", async (
+            string sourceId,
+            [FromServices] ISourceRegistry registry,
+            [FromServices] IJobCoordinator coordinator,
+            CancellationToken cancellationToken) =>
+        {
+            var source = registry.GetSource(sourceId);
+            if (source is null)
+            {
+                return HttpResults.NotFound(new { error = "source_not_found", sourceId });
+            }
+
+            var fetchKind = $"source:{sourceId}:fetch";
+            var result = await coordinator.TriggerAsync(fetchKind, null, "manual", cancellationToken).ConfigureAwait(false);
+
+            return result.Outcome switch
+            {
+                JobTriggerOutcome.Accepted => HttpResults.Accepted(null as string, new { sourceId, jobKind = fetchKind, outcome = "accepted", runId = result.Run?.RunId }),
+                JobTriggerOutcome.AlreadyRunning => HttpResults.Conflict(new { sourceId, jobKind = fetchKind, outcome = "already_running" }),
+                JobTriggerOutcome.NotFound => HttpResults.Ok(new { sourceId, jobKind = fetchKind, outcome = "no_job_defined", message = $"No fetch job registered for source '{sourceId}'" }),
+                _ => HttpResults.UnprocessableEntity(new { sourceId, jobKind = fetchKind, outcome = result.Outcome.ToString().ToLowerInvariant(), error = result.ErrorMessage })
+            };
+        })
+        .WithName("SyncSource")
+        .WithSummary("Trigger data sync for a single advisory source")
+        .WithDescription("Immediately triggers the fetch job for the specified source. Returns 202 Accepted with the job run ID, or 409 Conflict if already running.")
+        .Produces(StatusCodes.Status202Accepted)
+        .Produces(StatusCodes.Status404NotFound)
+        .Produces(StatusCodes.Status409Conflict)
+        .RequireAuthorization(SourcesManagePolicy);
+
+        // POST /sync — trigger data sync for all enabled sources
+        group.MapPost("/sync", async (
+            [FromServices] ISourceRegistry registry,
+            [FromServices] IJobCoordinator coordinator,
+            CancellationToken cancellationToken) =>
+        {
+            var enabledIds = await registry.GetEnabledSourcesAsync(cancellationToken).ConfigureAwait(false);
+            var results = new List<object>(enabledIds.Length);
+
+            foreach (var sourceId in enabledIds)
+            {
+                var fetchKind = $"source:{sourceId}:fetch";
+                var result = await coordinator.TriggerAsync(fetchKind, null, "manual-all", cancellationToken).ConfigureAwait(false);
+                results.Add(new
+                {
+                    sourceId,
+                    jobKind = fetchKind,
+                    outcome = result.Outcome.ToString().ToLowerInvariant(),
+                    runId = result.Run?.RunId
+                });
+            }
+
+            var accepted = results.Count(r => ((dynamic)r).outcome == "accepted");
+            return HttpResults.Ok(new { totalTriggered = accepted, totalSources = enabledIds.Length, results });
+        })
+        .WithName("SyncAllSources")
+        .WithSummary("Trigger data sync for all enabled advisory sources")
+        .WithDescription("Immediately triggers fetch jobs for every enabled source. Returns per-source trigger results.")
+        .Produces(StatusCodes.Status200OK)
+        .RequireAuthorization(SourcesManagePolicy);
+
         // GET /{sourceId}/check-result — get last check result for a source
         group.MapGet("/{sourceId}/check-result", (
             string sourceId,