Native Dagger container builds + Navidrome v0.61.1 (#330)

## Summary
- Move Dagger module from `.dagger/` to repo root (`src/blumeops/`), rename `blumeops-ci` → `blumeops`
- Replace opaque `docker_build()` with native Dagger pipelines that surface full build errors per step
- Migrate navidrome as the first container (`containers/navidrome/container.py`)
- Upgrade navidrome from v0.60.3 to v0.61.1 (major artwork overhaul, SQLite FTS5 search, server-managed transcoding)
- Add `dagger call container-version` for CI version extraction without Dockerfile parsing
- All mise tasks (`container-list`, `container-version-check`, `container-build-and-release`) updated for hybrid mode
- Legacy `docker_build()` fallback preserved for all other containers

## Motivation
When navidrome v0.61.0 added a new Go build tag (`sqlite_fts5`), `docker_build()` showed only "exit code: 1". We had to run `docker build --progress=plain` manually to find `undefined: buildtags.SQLITE_FTS5`. Native Dagger pipelines show the full error inline.

## Container build dispatch needed
After merge, dispatch container build for navidrome:
```
mise run container-build-and-release navidrome --ref 470b4bd
```

## Deploy steps
1. Wait for container build to complete
2. Back up navidrome-data PVC (non-reversible DB migrations)
3. `argocd app set navidrome --revision main && argocd app sync navidrome`
4. Verify at https://dj.ops.eblu.me

## Future
Remaining containers migrate incrementally in follow-up PRs using the same pattern.

Reviewed-on: #330

mise-tasks/service-review

@@ -21,7 +21,6 @@ After reviewing, update the service entry in the YAML file:
 Usage: mise run service-review [-- --limit 15] [-- --type argocd]
 """
 
-import sys
 from datetime import date
 from pathlib import Path
 from typing import Annotated
@@ -166,12 +165,25 @@ def main(
     ]
 
     svc_type = top_svc.get("type", "")
+    container_dir = Path(__file__).parent.parent / "containers" / top_svc["name"]
+    has_dockerfile_only = (
+        (container_dir / "Dockerfile").exists()
+        and not (container_dir / "container.py").exists()
+    )
+
     if svc_type == "argocd":
         checklist_parts += [
             "\n[bold]ArgoCD Deployment:[/bold]\n",
             "• Update image tag in argocd/manifests/<service>/kustomization.yaml\n",
             f"• Verify sync status: argocd app get {top_svc['name']}\n",
         ]
+        if has_dockerfile_only:
+            checklist_parts += [
+                "\n[bold yellow]Dagger Migration:[/bold yellow]\n",
+                "• This container still uses a Dockerfile (no container.py)\n",
+                "• Consider migrating to a native Dagger build for better error visibility\n",
+                f"• See containers/{top_svc['name']}/Dockerfile\n",
+            ]
     elif svc_type == "ansible":
         checklist_parts += [
             "\n[bold]Ansible Deployment:[/bold]\n",