feat: add Claude Code marketplace plugin with service and expert tiers
Add comprehensive Claude Code marketplace plugin supporting two paradigms
for managing markdown vaults:
- reme-service: Service-tier plugin with high-level MCP tools
(retrieve/remember/maintain) where reme2 internals handle R-M-W loop
- reme-expert: Expert-tier plugin where Claude Code agent runs R-M-W loop
directly using raw memory_* primitives guided by reme protocol skill
Both plugins implement identical 4-phase work paradigm:
- Recall: Retrieve relevant context with ranking by relevance/proximity
- Log: Record event facts and raw materials via idempotent event-folder upsert
- Distill: Promote events to topic graph via R-M-W loop
- Maintain: Vault hygiene sweep with lint and decay operations
Include marketplace configuration, documentation, MCP server setup,
subagents (reme-distiller, reme-curator), hooks (PreCompact, SessionEnd,
Stop), and slash commands (/reme-distill, /reme-recall, /reme-clean).
Remove outdated plugin entries from gitignore.
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