feat: add mixpanel and openstatus integrations and railway cloud connect

[claude]

Requested by boris · Slack thread

Before: OpenStatus and Mixpanel are live integrations on the platform, and Railway is a live cloud provider, but none of them could be connected from the CLI — polylane integration connect and polylane cloud connect simply did not offer them. After: all three are first-class picker entries with guided credential prompts and flags for non-interactive use.

This adds the two integrations the CLI was missing relative to the platform's live catalog (OpenStatus and Mixpanel) plus Railway cloud connect, mirroring the shape of the Conductor addition in #48.

How: openstatus joins the observability picker group with a single --api-key step (OpenStatus Settings → API Token, workspace-scoped key with write access, no prefix); it gets its own branch in connectWithCredentials so it does not print the code-agent autofix-executor note. mixpanel introduces a new product-analytics category and prompts for region (us|eu|in, matching the Mixpanel URL), service-account username and secret (Organization Settings → Service Accounts, Admin role; secret masked like other credentials), and a numeric project ID validated as a positive integer — the console's project auto-discovery route is hidden from the public API, so the CLI asks for the ID directly. railway joins the cloud provider list on the token path mirroring Fly: the production spec's cloud_accounts.connect union accepts {provider: "railway", token, railwayWorkspaceId?} (the console's OAuth flow relies on a hidden generate route and console callback, so it is not usable from the CLI); an optional --railway-workspace narrows the connect to one Railway workspace.

Analysis basis: compared the platform's integrations catalog at nominal 4f91b45 against the CLI at 36c6b0f. Missing-and-live: openstatus and mixpanel (both comingSoon: false with working connect handlers, and both payload variants already in the production OpenAPI spec / regenerated client), plus railway on the cloud surface. Excluded as comingSoon: true (no connect route, not in the spec): jira, pagerduty, triggerdev, hatchet, splunk, grafana, logfire, signoz, langsmith, braintrust, arize, linear, microsoft-teams, confluence, notion, gitlab, incident-io, circleci, amplitude, posthog, amp, and the coming-soon cloud providers (gcp, azure, runpod, and others). coding_agent stays excluded (comingSoon despite a live route).

Verification: npm run codegen, npm run typecheck, npm run lint, npm test (284 tests, all passing; category counts updated 12 → 14, observability list gains openstatus, new product-analytics category covered), plus a production build and node dist/polylane.mjs --version smoke test with --help output checks for both commands.

🤖 Generated with Claude Code

https://claude.ai/code/session_015DJ1B1PfT5wKMjZAkasFLq

---

Generated by Claude Code