Migrate PaymentMonitorService to dependency injection pattern

- Convert PaymentMonitorService to extend BaseService with proper metadata
- Add invoiceService property to BaseService for payment status checking
- Register PaymentMonitorService in market module with DI container
- Update market store to use injected service instead of singleton import
- Remove exported singleton instance from service file
- Add proper service initialization and cleanup in market module

This completes the third legacy service migration, following InvoiceService
and NostrmarketService. The service now properly integrates with the DI
architecture for better testing, lifecycle management, and loose coupling.

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

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

docs/.obsidian/workspace.json

@@ -13,12 +13,12 @@
             "state": {
               "type": "markdown",
               "state": {
-                "file": "01-architecture/index.md",
+                "file": "04-migrations/dependency-injection-migration.md",
                 "mode": "source",
                 "source": false
               },
               "icon": "lucide-file",
-              "title": "index"
+              "title": "dependency-injection-migration"
             }
           }
         ]
@@ -170,6 +170,7 @@
   },
   "active": "fe085d296b05d361",
   "lastOpenFiles": [
+    "01-architecture/index.md",
     "00-overview/index.md"
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 }