[UX] Define public tool surface and naming contract

[StatPan]

Parent: #60
Related: #48

Goal

Define the public AssemblyMCP tool surface before adding or renaming runtime tools.

This is the design gate for the KoreaLawMCP-inspired UX work. The output should be a concise public contract, not a long internal PRD.

Scope

• Audit the current public MCP tools in assemblymcp/server.py.
• Classify each tool as workflow, verification, lookup, discovery, or meta.
• Decide which existing workflow tools should be kept as-is, wrapped, renamed, or deprecated later.
• Decide whether [UX/RFC] Redesign AssemblyMCP tool experience using KoreaLawMCP patterns #60 complements or supersedes [RFC] MCP 도구 계층 재구조화 및 네이밍 컨벤션 정립 #48.
• Document naming rules for *_brief, *_timeline, *_impact_map, verify_*, search_*, and get_*.

Acceptance Criteria

• Current tool inventory is listed with categories.
• Target public tool groups are agreed.
• Naming rules are documented.
• Compatibility plan says which tools remain stable in the first implementation pass.
• Relationship to [RFC] MCP 도구 계층 재구조화 및 네이밍 컨벤션 정립 #48 is explicitly resolved.
• No runtime behavior changes are included in this ticket.