feat: Phase 2 data aggregation pipeline (Strike 4A)

Backend:
- Stats ingestion consumer subscribing to corrosion.*.stats NATS subject
- Hourly aggregation scheduler (runs :05 past every hour)
- Daily cleanup job (03:00 UTC) with 7-day raw / 90-day hourly retention
- Analytics API (summary, timeseries, CSV export)
- Complete stats DB queries with aggregation and cleanup

Frontend:
- Analytics dashboard with ECharts integration
- Player count and server performance charts
- Time range selector (24h/7d/30d)
- CSV export functionality
- Real-time data loading

Infrastructure:
- Exposed NatsBridge.jetstream for consumer access
- Background service initialization in main.rs

Data flow: Plugin → NATS → Consumer → DB → Aggregation → API → Charts

Unblocks Strike 4B (dashboards) and 4C (alerting).

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

CHANGELOG.md

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+# CHANGELOG — Corrosion Admin Panel
+
+All notable changes to this project will be documented in this file.
+
+## [Unreleased]
+
+### Added (Phase 2 — Data Aggregation Pipeline)
+
+**Backend:**
+- Stats ingestion consumer service (`stats_consumer.rs`) subscribing to `corrosion.*.stats` NATS subject
+- Complete stats database queries (`db/stats.rs`) with support for:
+  - Raw stats insertion and retrieval
+  - Hourly aggregation queries
+  - Analytics summary calculations (peak/avg players, uptime)
+  - Data retention cleanup (7 days raw, 90 days hourly)
+- Hourly stats aggregation scheduler job (runs at :05 past every hour)
+- Daily cleanup scheduler job (runs at 03:00 UTC)
+- Analytics API endpoints (`api/analytics.rs`):
+  - `GET /api/analytics/summary` — Peak/avg players, uptime percentage
+  - `GET /api/analytics/timeseries` — Time-series data for charting (hourly/raw granularity)
+  - `GET /api/analytics/export` — CSV export of server stats
+- Background service initialization in main.rs (stats consumer + scheduler)
+
+**Frontend:**
+- Analytics TypeScript types (`AnalyticsSummary`, `TimeseriesData`, `HourlyStats`)
+- Complete `AnalyticsView.vue` implementation with:
+  - Real-time data fetching from analytics API
+  - Apache ECharts integration for Player Count and Server Performance charts
+  - Time range selector (24h/7d/30d)
+  - CSV export functionality
+  - Loading states and responsive layout
+
+**Infrastructure:**
+- Made `NatsBridge.jetstream` public for service consumer access
+
+### Technical Details
+
+**Data Flow:**
+```
+Plugin/Agent publishes stats (60s interval)
+  → NATS JetStream (corrosion.*.stats)
+  → StatsConsumerService persists to server_stats table
+  → Hourly aggregation job rolls up to server_stats_hourly
+  → Analytics API queries aggregated data
+  → Frontend renders charts via ECharts
+```
+
+**Database Schema:**
+- `server_stats` table (raw stats, 7-day retention)
+- `server_stats_hourly` table (aggregated hourly data, 90-day retention)
+
+**Scheduler Jobs:**
+- Hourly aggregation: `0 5 * * * *` (at :05 past every hour)
+- Daily cleanup: `0 0 3 * * *` (at 03:00 UTC)
+
+### Installation Notes
+
+**Frontend:**
+```bash
+cd frontend && npm install echarts
+```
+
+**Backend:**
+No additional dependencies beyond existing `Cargo.toml`.
+
+### Deferred to Phase 2.2
+
+- Player retention tracking (new vs returning players, session duration)
+- Wipe-correlated analytics
+- Player activity heatmaps (time-of-day patterns)
+- Anomaly alerting system
+
+---
+
+## [2025-02-15] — Phase 1 Complete
+
+### Added (Phase 1 — Foundation)
+
+**Backend Services:**
+- Core control plane (Axum + Tokio)
+- Auto-wiper with rollback (`wipe_engine.rs`)
+- Plugin management system
+- WebSocket/NATS bridge for real-time data
+- Companion agent adapter (bare metal server management)
+- Panel adapters (AMP + Pterodactyl)
+
+**Frontend:**
+- Vue 3 dashboard with 19 admin sub-views
+- Wipe management UI with real-time progress
+- Toast notification system
+- Plugin management interface
+- Public server site
+
+**Infrastructure:**
+- PostgreSQL schema (migrations 001-003)
+- NATS JetStream streams (6 streams configured)
+- Docker Compose deployment (4 services)
+- JWT auth with refresh tokens, TOTP 2FA
+
+**Companion Agent:**
+- Go binary for bare metal server management
+- NATS-based command execution
+- Process lifecycle control
+- File operations support
+
+**uMod Plugin:**
+- C# plugin for Rust game server integration
+- Stats publishing every 60 seconds
+- Server lifecycle event reporting
+
+### Commits
+
+- `c5d0571` — feat: Complete Phase 1 frontend — WebSocket + Wipe feature end-to-end
+- `590765f` — feat: Complete Phase 1 backend services and WebSocket/NATS bridge
+- `8320591` — docs: Update companion agent language choice to Go
+- `3c39345` — docs: Add CLAUDE.md and Claude Code settings
+- `81eeb3b` — docs: Add AGENTS.md roster and resource discipline
+
+---
+
+**Format:** `type: Short description`
+
+**Types:** feat, fix, docs, refactor, test, chore, perf, ci