feat: provider integration harness and models.dev catalog

[EmersonBraun]

Summary

• add transport-injected adapter contract coverage and a provider capability matrix
• add a shared provider registry and doctor diagnostics for CLI integrations
• add DeepSeek, Grok, Kimi, Groq, and OpenRouter provider defaults and init scaffolding
• refresh the models.dev-backed catalog to 184 providers and 6,293 models with normalized provenance, lifecycle, reasoning, limits, and pricing metadata
• add offline snapshot freshness checks, live drift detection, and weekly CI monitoring
• add explicit native / OpenAI-compatible / unsupported provider classification
• reject newly introduced nested ternaries and refactor the affected CLI paths
• regenerate canonical docs, ecosystem statistics, public API metadata, and changeset
• merge the latest main and regenerate the doc-bridge artifacts to clear the PR conflict
• refresh the public API baseline for the two intentional catalog exports

Validation

• pnpm check:quality-gates — 37/37 gates passed after merging main and refreshing the public API baseline
• pnpm check:public-api-snapshot — passed with 22 packages, 63 subpaths, and 1,708 symbols
• pnpm lint — 56 tasks passed in the pre-push hook
• pnpm build — 42 tasks passed in the pre-push hook
• pnpm --filter @agentskit/adapters test — 522 tests passed
• pnpm docs:bridge:gate — passed with content hash 4b8372dc800cc78266ddc77be7184f5451bcfa6a91c36f3ef631f6119733c5e6
• models.dev live freshness check passed with content hash d0a8593671235ebb2b08262f7532c39b733d67def3ea62180795307500416ce3
• pre-push hook passed without bypass

Published head commit: 3c8b498ea8f54550045ac1d4891372f583c4cf9e

Approved diff digest relative to current main: 1b9dda2097c94b9f50389c3bca8b45d16bd0b2e668e925f4b165f66bbfc954d0

No secrets or provider credentials are included. The pull request is ready for human review.

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