add conservative AnyAPI sync provider

[es697]

Adds a conservative anyapi sync provider backed by AnyAPI's /v1/models endpoint.

• requires ANYAPI_API_KEY for sync runs and wires it into the sync workflow
• registers AnyAPI in the aggregator sync group
• treats the endpoint as ID-only: skips auto-creating new models and never deletes missing ones
• preserves existing hand-authored AnyAPI TOMLs
• renames existing AnyAPI model paths that need to match current API IDs

Verified against the live AnyAPI API on 2026-07-13:

• present in /v1/models: anthropic/claude-haiku-4.5
• present in /v1/models: anthropic/claude-sonnet-4.5
• present in /v1/models: anthropic/claude-sonnet-4.6
• present in /v1/models: anthropic/claude-opus-4.6
• present in /v1/models: anthropic/claude-opus-4.7
• present in /v1/models: x-ai/grok-4.3
• absent from /v1/models: anthropic/claude-haiku-4-5, anthropic/claude-sonnet-4-5, anthropic/claude-sonnet-4-6, anthropic/claude-opus-4-6, anthropic/claude-opus-4-7, xai/grok-4.3

[github-actions]

Action items

• [low] [possible mistake] providers/anyapi/models/anthropic/claude-haiku-4.5.toml:1 (and the other five renamed paths) - Check: Renamed AnyAPI model paths must equal the id values returned by https://api.anyapi.ai/v1/models. Why: The PR renames claude-haiku-4-5→claude-haiku-4.5, claude-opus-4-6→claude-opus-4.6, claude-opus-4-7→claude-opus-4.7, claude-sonnet-4-5→claude-sonnet-4.5, claude-sonnet-4-6→claude-sonnet-4.6, and xai/grok-4.3→x-ai/grok-4.3. Filenames are the public model IDs used for AI SDK lookups, and the new sync's translateModel/sourceID only reconcile files whose path matches the API id (everything else is skipped or merely retained via skipCreates/deleteMissing: false). The PR body asserts the renames "need to match current API IDs" but cites no source, so the exact IDs cannot be verified here; a mismatch would strand the renamed files (kept but never updated) and break consumers referencing the old IDs. The dotted Anthropic and x-ai/ conventions match peer aggregators (openrouter, kilo, crossmodel, vercel), which supports the change but does not prove it. Action: Provide an AnyAPI /v1/models response or documentation snippet confirming these exact six IDs, and cite it in the PR body.

[es697]

Confirmed from the live AnyAPI /v1/models response used when preparing the original PR: anthropic/claude-haiku-4.5, anthropic/claude-sonnet-4.5, anthropic/claude-sonnet-4.6, anthropic/claude-opus-4.6, anthropic/claude-opus-4.7, and x-ai/grok-4.3 are present there; the dashed Anthropic paths and xai/grok-4.3 are absent. I added that verification to the PR body as well.