Add service/API for querying the analyses

Our analysis suggestion can interact directly on the flat analyses lists in a project, but we want to expose those to other extensions. Once we have a defined API for querying the analyses, the internal analysis suggestion should use it too.

Contract checklist (2026-07 audit): before the API is public:

• #137: schema version on persisted/returned records.
• Decide typed payloads vs. JSON strings over the command bus (all current commands pass JSON strings; a network-object service like lexicon.entryService would give typed signatures).
• Validate enum values (Confidence, AssignmentStatus) at the boundary (#140).
• Define query shape: by token ref(s), by surface form (normalized — the suggestion pool's normalization should be part of the contract), by book, by status.
• Read-only first; mutation API is a separate decision.

Size: M

Start with the internal analysis suggestion and compare its flat-list access with the network-object pattern used by lexicon.entryService. Resolve the contract checklist decisions for schemas, payloads, enum validation, query shapes, and read-only behavior. Done means a defined public API that other extensions can query and that the internal suggestion can use.