docs: gaze multi-language support — external analyzer protocol and new CLI flags

[yvonnedevlinrh]

Context

PR unbound-force/gaze#178 adds a JSON-RPC 2.0 external analyzer protocol enabling multi-language support in Gaze.

What changed

• New --analyzer <binary> and --language <lang> CLI flags on gaze crap, gaze quality, and gaze report
• New analyzers section in .gaze.yaml for config-based analyzer discovery
• Three-tier analyzer discovery: CLI flag → .gaze.yaml → PATH convention (gaze-analyzer-<lang>)
• New docs/protocol.md in-repo — full JSON-RPC protocol specification for external analyzer authors
• Gaze is no longer Go-only in principle

What needs updating

• Add a "Multi-language support" section covering the external analyzer concept
• Document the two new CLI flags (--analyzer, --language) in the CLI reference table
• Document the .gaze.yaml analyzers: configuration block
• Document the three-tier analyzer discovery chain
• Link to or surface the in-repo docs/protocol.md for analyzer authors

Affected pages

• content/docs/projects/gaze.md — CLI flags table (lines ~145–175), architecture section
• Any getting-started guide for Gaze

[yvonnedevlinrh]

Scope correction: --analyzer not supported on gaze quality

The "What changed" section lists --analyzer and --language flags on gaze crap, gaze quality, and gaze report. However, gaze quality explicitly rejects --analyzer with the error:

--analyzer is not yet supported for 'gaze quality'

The flags are registered on the quality command but hidden from help output. Only gaze crap and gaze report support external analyzers today.

The original feature issue (gaze#95) included quality in scope, and the Phase 1 refactor (gaze#165) extracted provider interfaces from the quality package, but the Phase 2 implementation (gaze#178) deliberately deferred it. The "not yet" phrasing suggests future intent — this is now tracked in gaze#229.

When writing the website docs, only document --analyzer/--language support on gaze crap and gaze report. Documenting support on gaze quality would violate Constitution Principle I (Content Accuracy). If gaze#229 concludes that quality support should be added, the docs can be updated after that implementation ships.