feat(integrations): add posthog Stripe catalog provider

[snowmead]

Summary

• Adds the posthog Stripe Projects catalog integration family as CatalogResource adapter(s).
• Follows docs/ADDING-A-PROVIDER.md and docs/PROVIDER-WAVES.md.
• Includes gap test + hermetic provision test. OUTPUT_FIELDS provisional until mise run discover.

Test plan

• Gap + hermetic tests in module
• Live mise run discover when provider is linked
• Merge after resolving additive registry.rs conflict with other family PRs

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Note

Low Risk
Follows the established CatalogResource pattern with offline tests only; SDK helpers are additive and PostHog output names remain provisional until discover.

Overview
Introduces PostHog as a managed Phase 1 catalog integration: PostHogAnalytics for posthog/analytics exposes ${integrations.*.api_key} from provisional POSTHOG_API_KEY output mapping, with catalog gap and hermetic provision tests, registry registration, and an outputs drift test alongside existing Cloudflare providers.

Provider SDK gains int_optional, bool_required, and bool_optional on shared provision config parsing so generated catalog adapters can read non-string schema fields.

Docs/process: new PROVIDER-WAVES.md and a catalog-first decision in DECISIONS; ADDING-A-PROVIDER links to waves. scripts/generate_catalog_integrations.py scaffolds remaining deployables from catalog.json (registry/mod updates, output hints including PostHog).

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Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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Generator skips posthog in IMPLEMENTED

Medium Severity

This commit adds a hand-written posthog/analytics adapter but leaves posthog/analytics out of the generator’s IMPLEMENTED set. Running generate_catalog_integrations.py still treats that service as unimplemented, so it can overwrite providers/posthog/analytics.rs and rebuild providers/mod.rs and register_providers! without the manual registration.

 

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