docs: Add Sentry deployment documentation

- Create docs/sentry.md: Complete Sentry self-hosted deployment guide
  * Architecture overview with distributed system components
  * Core services: Relay, Kafka, Snuba, ClickHouse, PostgreSQL, Redis, SeaweedFS
  * Data flow and storage requirements
  * Management via slcompose orchestrator
  * Backup requirements documentation

- Update AI_CONTEXT.md: Add Sentry to core services
  * List Sentry as error tracking & observability platform
  * Add sentry.silveressence.net domain mapping

- Update README.md: Add Sentry to running services
  * Include in comprehensive services list

- Update roadmap.md: Mark Sentry as completed
  * Move from planned to completed section
  * Document all deployed components
  * List completed validation items
  * Reference deployment documentation

- Update services.md: Full Sentry service documentation
  * Add running Sentry service section
  * Document architecture, networking, and management
  * Remove from Phase 2 planned deployments
  * Link to detailed deployment guide

docs/services.md

@@ -461,6 +461,62 @@ Operational
 
 ---
 
+### Sentry
+
+URL:
+
+```text
+https://sentry.silveressence.net
+```
+
+Purpose:
+
+* Centralized error tracking and observability
+* Application exception diagnostics
+* Release health visibility
+* Performance monitoring
+
+Architecture:
+
+* Distributed system with 70+ services
+* Components: Relay, Kafka, Snuba, ClickHouse, PostgreSQL, Redis, SeaweedFS
+* Self-hosted deployment
+
+Networks:
+
+* `proxy` for Nginx Proxy Manager access
+* `sentry-self-hosted_default` for internal service communication
+
+Management:
+
+* Managed via slcompose orchestrator
+* Automated Infisical secret injection
+* Single atomic deployment unit
+
+Data Storage:
+
+* PostgreSQL for metadata
+* ClickHouse for high-performance event storage
+* Redis for caching and coordination
+* SeaweedFS for attachments and objects
+
+Backup Requirements:
+
+* PostgreSQL database volume
+* ClickHouse data volume
+* Sentry configuration files
+* Persistent Kafka data (if enabled)
+
+Status:
+
+```text
+Running
+```
+
+See [docs/sentry.md](sentry.md) for complete deployment documentation.
+
+---
+
 ### Xray (Direct Production)
 
 Purpose:
@@ -695,7 +751,6 @@ Phase 1:
 Phase 2:
 
 * CrowdSec
-* Sentry
 * Restic
 * Fail2Ban upgrade
 * Cloudflare rate limiting and WAF