feat: add iHerb providers (Partnerize, Impact, Apify)

[CodeWithJuber]

Summary

Add iHerb as provider #22–24. Since iHerb has no public first-party API, coverage comes from three independent sources — each a separate provider with its own auth and base URL:

• iherb_partnerize — Partnerize affiliate network API (8 operations): campaigns, commissions, conversions, product feeds, tracking links, click reports, performance stats. HTTP Basic auth (IHERB_PARTNERIZE_APP_KEY + IHERB_PARTNERIZE_USER_KEY).
• iherb_impact — Impact affiliate network API (8 operations): campaigns, actions, catalogs, catalog items, tracking links, promo codes. HTTP Basic auth (IHERB_IMPACT_ACCOUNT_SID + IHERB_IMPACT_AUTH_TOKEN).
• iherb_apify — Apify iHerb scraper API (7 operations): product search, product details, reviews, price monitoring, run status, dataset results, run history. Bearer token auth (IHERB_APIFY_TOKEN).

Totals move from 21 → 24 providers and 278 → 301 operations.

Changes

File	Change
specs/iherb_partnerize.json	New OpenAPI 3.0.3 spec (8 ops)
specs/iherb_impact.json	New OpenAPI 3.0.3 spec (8 ops)
specs/iherb_apify.json	New OpenAPI 3.0.3 spec (7 ops)
crates/hub-auth/src/store.rs	3 new auth blocks in from_env()
README.md	3 new provider rows, updated totals

Validation

• Formatting and lint checks pass.
• Type checks pass.
• Unit tests pass (26/26).
• Integration tests were run, or are not applicable.
• Documentation and data-source references are updated.

connector-hub validate confirms: 301 operations across 24 providers, all specs parse, no duplicate IDs, plugin manifests at version 2.0.0.

Security and operations

• No credentials, tokens, customer data, or generated .env files are included.
• New network calls have timeouts, bounded retries, validation, and rate-limit handling.
• Breaking changes, deployment steps, and rollback steps are documented.

No breaking changes. All three providers use the existing NetClient HTTP path (SSRF-validated, IP-pinned, bounded retries). Auth follows established patterns (Basic / Bearer).

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Generated by Claude Code