[Docs] Note 1M context window for latest Claude models on Anthropic provider page

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​Opened on behalf of @taltas. Follow up by mentioning @roomote, in the web UI, or in Discord.

What changed

Updates the Anthropic provider page's "Context Window" tip under "Tips and Notes": it previously stated Claude models have 200,000-token context windows, which is stale for the latest generation. The tip now notes that the latest Claude models (such as Claude Sonnet 5.5) support a 1 million token context window.

Why this change was made

Claude Sonnet 5.5 was added to Zoo Code's model providers in the paired Zoo-Code PR, and the provider docs' context-window note predates the 1M-context Claude generation (Sonnet 5, Opus 5/5.5, Sonnet 5.5). The provider docs intentionally defer to Anthropic's model documentation for version-specific model lists, so this is the only statement that needed updating.

Impact

Readers of the Anthropic provider page see an accurate context-window claim for current Claude models. No structural, navigational, or code changes; one bullet reworded.

Validated with pnpm run check-types and a full pnpm build (both green).

Screenshots

Related PRs

• [Feat] Add Claude Sonnet 5.5 to model providers Zoo-Code#1849: [Feat] Add Claude Sonnet 5.5 to model providers — [Feat] Add Claude Sonnet 5.5 to model providers Zoo-Code#1849