feat: PostHog product analytics (#58)

* wip: posthog analytics

* wip: remove posthog-rs crate; call endpoint directly

* make analytics non-blocking

* session start event

* configure analytics for release builds

* remove dev_server_stopped event

* address review comments

* simplify analytics enabled logic

* analytics on by default; send start_session when user enables analytics; new task_attempt_start event

* lower visibility of analytics logs

* chore: bump version to 0.0.37-0

* set analytics to true if previously unset

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Co-authored-by: GitHub Action <action@github.com>

backend/Cargo.toml

@@ -45,8 +45,10 @@ octocrab = "0.44"
 sentry = { version = "0.41.0", features = ["anyhow", "backtrace", "panic", "debug-images"] }
 sentry-tower = "0.41.0"
 sentry-tracing = { version = "0.41.0", features = ["backtrace"] }
+reqwest = { version = "0.11", features = ["json"] }
 
 [build-dependencies]
+dotenv = "0.15"
 ts-rs = { version = "9.0", features = ["uuid-impl", "chrono-impl"] }
 
 [profile.release]