feat: add Clearbit integration (person/company enrichment + autocomplete)

[jackulau]

Summary

Adds a Clearbit API integration covering the three operations specified in issue #15: person enrichment, company enrichment, and company autocomplete. Resolves #15.

Operations

Node	Endpoint	Purpose
clearbitEnrichPerson	GET https://person-stream.clearbit.com/v2/people/find	Enrich a person by email (optional: given/family name, company, company domain, linkedIn, twitter)
clearbitEnrichCompany	GET https://company-stream.clearbit.com/v2/companies/find	Enrich a company by domain
clearbitCompanyAutocomplete	GET https://autocomplete.clearbit.com/v1/companies/suggest	Suggest companies from a partial name

Credential

Single API-key credential (clearbit) authenticating via Authorization: Bearer {{apiKey}} header, defined through defineApiKeyCredential from @jam-nodes/core. Matches the shape declared in issue #15 exactly.

Implementation notes

• Streaming endpoints. Uses Clearbit's person-stream / company-stream subdomains instead of the non-streaming alternatives, because the non-streaming endpoints return 202 + webhook callback (unsuitable for synchronous workflow execution). Matches the n8n reference implementation.
• CamelCase → snake_case URL mapping. Input fields (givenName, familyName, companyDomain) are mapped to Clearbit's snake_case query params (given_name, family_name, company_domain). The linkedIn field specifically maps to lowercase linkedin to match Clearbit's URL convention.
• Autocomplete name → query. The issue's input field is name but Clearbit's URL param is query; mapped at request-build time.
• Response mapping. Clearbit returns richer objects than issue [Integration] Clearbit - Person and company enrichment #15 asks for; output schemas extract only the fields the issue specifies. Nullable fields (location, employment.title, social.github, etc.) are handled with ?? null and tested explicitly against sparse responses.
• File per operation. clearbit-enrich-person.ts, clearbit-enrich-company.ts, clearbit-company-autocomplete.ts, each self-contained — follows the apify / devto precedent.
• HTTP layer. Uses the shared fetchWithRetry utility (default: 3 retries, 1s initial backoff, 30s timeout). No retry/cache/timeout configuration inside node bodies — nodes stay pure per the architectural rule in CLAUDE.md.
• Error handling. All three nodes return { success: false, error } on missing credentials, non-OK responses, malformed responses (missing id), and network failures. They never throw.

Files changed

• packages/core/src/types/node.ts — extend NodeCredentials with clearbit?: { apiKey: string }
• packages/nodes/src/integrations/clearbit/credentials.ts — new, clearbitCredential
• packages/nodes/src/integrations/clearbit/schemas.ts — new, 6 Zod schemas + 6 inferred types
• packages/nodes/src/integrations/clearbit/clearbit-enrich-person.ts — new node
• packages/nodes/src/integrations/clearbit/clearbit-enrich-company.ts — new node
• packages/nodes/src/integrations/clearbit/clearbit-company-autocomplete.ts — new node
• packages/nodes/src/integrations/clearbit/index.ts — new barrel
• packages/nodes/src/integrations/clearbit/__tests__/clearbit.test.ts — new, 50 tests
• packages/nodes/src/integrations/index.ts — re-export clearbit
• packages/nodes/src/index.ts — add value + type exports, append to builtInNodes[]

Test coverage (50 tests, all passing)

• Credential (5): name/type/displayName, header Bearer authentication, documentation URL, schema accepts {apiKey}, schema rejects {}
• Schemas (10): required-field validation + empty-string rejection + optional-field acceptance for all 3 operations
• clearbit_enrich_person (13): missing API key, full happy path, endpoint URL, Bearer header, email query param, camelCase→snake_case mapping, linkedIn→linkedin lowercase, omitting absent optionals, nullable response fields, missing nested social objects, 401, 404, missing-id guard, network failure
• clearbit_enrich_company (11): missing API key, happy path, endpoint URL, Bearer header, category mapping, metrics mapping with nulls, absent social platforms, 401, 404, missing-id guard, network failure
• clearbit_company_autocomplete (8): missing API key, happy path, endpoint URL, name→query param mapping, Bearer header, empty results, non-OK response, malformed (non-array) response, network failure
• Integration (1): all 3 nodes return structured context.credentials.clearbit.apiKey error when credentials are absent

Verification

$ npm --workspace=@jam-nodes/nodes test
Test Files  10 passed (10)
     Tests  245 passed (245)
  Duration  10.72s

• Full suite: 245/245 passing, zero regressions vs main baseline
• Clearbit test file alone: 50/50 passing
• tsc --noEmit scoped to clearbit files, integrations/index.ts, nodes/src/index.ts, types/node.ts: zero errors (pre-existing unrelated typecheck errors in apify/, google-sheets/, slack/ are untouched)

Acceptance criteria (from issue #15)

• Credential definition
• All 3 operations
• Zod schemas
• Unit tests

Closes #15