Synchronize product documentation with current mainline capabilities

[bearmug]

Problem

The README and public landing page have drifted from the current product. The landing page still advertises 75+ metrics and 7 strategies, while mainline documents 100+ fields, 14 presets, strict preset files, search, metainfo, and TA ranking. The distinction between Claude Code commands and generic MCP-client functionality is also unclear.

Scope

• Update repository README/API/development docs for current tool counts and preset-file behavior.
• Document structured output, provenance, partial-result semantics, and upstream limitations after the implementation PRs land.
• Remove stale examples and claims.
• Open a linked cross-repository follow-up for fiale-plus.github.io landing-page synchronization.

Acceptance criteria

• Repository docs match the actual tool list, defaults, operator value shapes, and CLI behavior.
• Unofficial/public-endpoint limitations are visible at the point of setup.
• No claim says 75+ metrics or 7 strategies.
• Documentation references the supported MCP/CLI surfaces accurately.

Non-goals

No product feature expansion or redesign of the external website in this repository.