MCP resources: expose status, profile, savings, and index overview without extra tool calls

[willwashburn]

Problem

Some context is useful to the client or model before a specific tool call: active profile, learning mode, savings summary, index status, and available files or languages. Today this information is only available through tool calls or local files, which increases friction and can create unnecessary turns.

Goal

Expose read-only MCP resources for stable project and Wash metadata.

Proposed resources

• relaywash://status - server version, tool count, active session id when known.
• relaywash://profile - active profile summary with sensitive data omitted.
• relaywash://savings - current session and aggregate savings summary.
• relaywash://index - optional index status and freshness.
• relaywash://files - indexed file list when an index exists.

Acceptance criteria

• Server advertises resources/list and resources/read capabilities.
• Resources are read-only and never mutate ledger or profile state.
• Missing optional data returns a useful empty state rather than an error.
• Tests cover resources list, each resource read, and unknown resource errors.
• Resource output is bounded and safe to include in model context.

Implementation notes

Add this after core metadata and profile work so resources can reuse existing summary helpers. Keep resource names project-specific under the relaywash:// scheme.