feat: add OpenAPI-generated API client

[mekilis]

Summary

• Adds a generated /api/v1 client under src/Client/ (namespace Convoy\Client, mapped by the existing PSR-4 rule) via OpenAPI Generator (pinned 7.23.0), generated from docs/v3/openapi3.yaml on frain-dev/convoy main. The hand-written SDK (rest of src/, incl. webhook verify) is untouched by generation.
• sdk_generation.yaml matches the frain-dev/convoy dispatcher contract (same workflow filename and inputs as the other SDK repos): regenerates, runs the test suite, then opens a PR only when the client changed.
• ci.yml adds GitHub Actions tests — this repo previously had no CI, so generation PRs would have had no gate.
• Offline contract tests (Guzzle MockHandler) prove verb, path, auth header, X-Convoy-Version pin, JSON body, and that arbitrary event data payloads round-trip without dropping keys.
• composer: php ^8.1 + Guzzle for the generated client; the hand-written PSR-18 stack is unchanged.

Test plan

• composer test (pest) — 34 tests green (shared signature vectors + webhook + routes + 2 new contract tests)

---

Note

Medium Risk
Large generated surface and a breaking PHP minimum (^8.1) plus new Guzzle dependency affect consumers; generation workflow has write/PR permissions but targets isolated branches with pre-PR tests.

Overview
Adds a generated /api/v1 client under Convoy\Client (src/Client/) from Convoy’s OpenAPI spec via pinned OpenAPI Generator 7.23.0 and scripts/generate.sh (checksum-verified JAR, rsync into src/Client/ only). The existing hand-written PSR-18 SDK and webhook code stay unchanged.

Automation: ci.yml runs composer test on push/PR. sdk_generation.yaml regenerates on schedule/dispatch (aligned with other Convoy SDK repos), runs tests, and opens a PR only when the client diff is non-empty (validated feature_branch, optional SDK_BOT_PAT).

Package: composer.json bumps minimum PHP to ^8.1 and adds Guzzle for the generated client. README documents the generated client usage and regeneration.

Tests: New offline contract tests (Guzzle MockHandler) assert verb, path, auth, X-Convoy-Version, JSON body, and event data round-trip for the generated client.

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Stale comment

Security review found 1 net-new actionable issue on the current head.

  

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