feat: Posthog integration (#9077)

# Which Problems Are Solved

- Adds a service in the console to enable Posthog integration based on
upon user environment variables

# How the Problems Are Solved

- A new service has been created in console for posthog
- This is only initiated based upon provided environment variables

# Additional Changes

N/A

# Additional Context

- Closes #[9076](https://github.com/zitadel/zitadel/issues/9076)
- Cannot be merged until this is completed
#[9070](https://github.com/zitadel/zitadel/issues/9070)

console/package.json

@@ -47,6 +47,7 @@
     "moment": "^2.29.4",
     "ngx-color": "^9.0.0",
     "opentype.js": "^1.3.4",
+    "posthog-js": "^1.191.0",
     "rxjs": "~7.8.0",
     "tinycolor2": "^1.6.0",
     "tslib": "^2.7.0",