major: kestrel is now a tak server (#6)

## Added

- CoT (Cursor on Target) server on port 8089 enabling ATAK/iTAK device connectivity
- Support for TAK stream protocol and traditional XML CoT messages
- TLS/SSL support with automatic fallback to plain TCP
- Username/password authentication for CoT connections
- Real-time device position tracking with TTL-based expiration (90s default)
- API endpoints: `/api/cot/config`, `/api/cot/server-package`, `/api/cot/truststore`, `/api/me/cot-password`
- TAK Server section in Settings with QR code for iTAK setup
- ATAK password management in Account page for OIDC users
- CoT device markers on map showing real-time positions
- Comprehensive documentation in `docs/` directory
- Environment variables: `COT_PORT`, `COT_TTL_MS`, `COT_REQUIRE_AUTH`, `COT_SSL_CERT`, `COT_SSL_KEY`, `COT_DEBUG`
- Dependencies: `fast-xml-parser`, `jszip`, `qrcode`

## Changed

- Authentication system supports CoT password management for OIDC users
- Database schema includes `cot_password_hash` field
- Test suite refactored to follow functional design principles

## Removed

- Consolidated utility modules: `authConfig.js`, `authSkipPaths.js`, `bootstrap.js`, `poiConstants.js`, `session.js`

## Security

- XML entity expansion protection in CoT parser
- Enhanced input validation and SQL injection prevention
- Authentication timeout to prevent hanging connections

## Breaking Changes

- Port 8089 must be exposed for CoT server. Update firewall rules and Docker/Kubernetes configurations.

## Migration Notes

- OIDC users must set ATAK password via Account settings before connecting
- Docker: expose port 8089 (`-p 8089:8089`)
- Kubernetes: update Helm values to expose port 8089

Co-authored-by: Madison Grubb <madison@elastiflow.com>
Reviewed-on: #6

test/unit/constants.spec.js

@@ -0,0 +1,40 @@
+import { describe, it, expect } from 'vitest'
+import {
+  COT_AUTH_TIMEOUT_MS,
+  LIVE_SESSION_TTL_MS,
+  COT_ENTITY_TTL_MS,
+  POLL_INTERVAL_MS,
+  SHUTDOWN_TIMEOUT_MS,
+  COT_PORT,
+  WEBSOCKET_PATH,
+  MAX_PAYLOAD_BYTES,
+  MAX_STRING_LENGTH,
+  MAX_IDENTIFIER_LENGTH,
+  MEDIASOUP_RTC_MIN_PORT,
+  MEDIASOUP_RTC_MAX_PORT,
+} from '../../server/utils/constants.js'
+
+describe('constants', () => {
+  it('uses default values when env vars not set', () => {
+    expect(COT_AUTH_TIMEOUT_MS).toBe(15000)
+    expect(LIVE_SESSION_TTL_MS).toBe(60000)
+    expect(COT_ENTITY_TTL_MS).toBe(90000)
+    expect(POLL_INTERVAL_MS).toBe(1500)
+    expect(SHUTDOWN_TIMEOUT_MS).toBe(30000)
+    expect(COT_PORT).toBe(8089)
+    expect(WEBSOCKET_PATH).toBe('/ws')
+    expect(MAX_PAYLOAD_BYTES).toBe(64 * 1024)
+    expect(MAX_STRING_LENGTH).toBe(1000)
+    expect(MAX_IDENTIFIER_LENGTH).toBe(255)
+    expect(MEDIASOUP_RTC_MIN_PORT).toBe(40000)
+    expect(MEDIASOUP_RTC_MAX_PORT).toBe(49999)
+  })
+
+  it('handles invalid env var values gracefully', () => {
+    // Constants are evaluated at module load time, so env vars set in tests won't affect them
+    // This test verifies the pattern: Number(process.env.VAR) || default
+    const invalidValue = Number('invalid')
+    expect(Number.isNaN(invalidValue)).toBe(true)
+    expect(invalidValue || 15000).toBe(15000)
+  })
+})