feat: presets + installer + CLI subcommands

[marceloceccon]

Summary

Consumer-side half of the v0.11 work. Adds five task-tuned preset MCP tools, a host-detecting install subcommand for the top three IDE/host environments (Claude Code, Cursor, Windsurf), and an MCP-registry manifest. Backward compatible end-to-end: existing 0.10 host configs and the generic consensus tool are byte-identical to before, and a bare ai-consensus-mcp --config X still works exactly as it did.

The matching tool-calling integration is deferred until ai-consensus-core@0.11.0 merges and publishes — see Phase 3 in progress.md. This PR covers Phases 0/1/4; Phase 2 lives upstream; Phase 3 unblocks once the core ships.

What ships in this PR

Five preset MCP tools

Each preset is registered as its own tool so MCP hosts surface them in autocomplete:

Tool	Panel	Rounds	Temp	Output
consensus_code_review	pessimist + domain-expert + devils-advocate + first-principles	3	0.3	BLOCKER/MAJOR/MINOR/NIT findings + recommended fixes
consensus_architecture_debate	first-principles + domain-expert + vc-specialist + pessimist	4	0.6	Decision matrix + recommendation + flip conditions
consensus_research_synthesis	scientific-skeptic + domain-expert + first-principles + optimistic-futurist	4	0.4	Citation-first claims with HIGH/MEDIUM/LOW confidence
consensus_decision_making	vc-specialist + pessimist + domain-expert + devils-advocate	4	0.5	Ranked options with EV / risks / upsides
consensus_debug_postmortem	pessimist + domain-expert + first-principles + scientific-skeptic	3	0.3	Postmortem report (timeline, 5-whys, remediation)

Implementation: src/presets/{types,registry,resolve-panel,build-input-schema,format}.ts plus src/presets/definitions/*.ts. Panel resolution is non-destructive — preset task suffixes are appended to fresh persona objects, never mutating the global PERSONAS table. Fallback chains and a used-persona guard prevent double-binding. Snapshot tests lock the resolved system prompts (6 inline snapshots).

Preset tools deliberately do not expose participantIds — the panel is the preset's responsibility. If your config can't satisfy a preset's required personas, the tool description prefixes ⚠ Currently NOT RUNNABLE and the tool-call error names the missing personas.

Installer subcommand

ai-consensus-mcp install --config /abs/path/to/consensus.config.json

Detects Claude Code / Cursor / Windsurf and registers an entry in each one's mcpServers map. Atomic write (write-to-tmp, rename), never clobbers siblings (Claude Code's .claude.json holds far more than mcpServers), idempotent (re-runs report alreadyPresent), refuses to overwrite a different existing entry without --force. Tested with mkdtemp-rooted fake \$HOME directories so CI runs without touching the real home.

Flags: --hosts, --name, --command, --force, --list-hosts, --help. The bare ai-consensus-mcp --config X invocation still routes to serve (full backward compat with 0.10).

Foundations

• ESLint v10 (flat config) + typescript-eslint v8 + Prettier v3.8 — npm run lint, npm run format:check, npm run check
• vitest 2.1.8 → 4.1.5 (clears 6 moderate audit findings via esbuild < 0.24.2; aligns with upstream)
• Coverage thresholds in vitest.config.ts with a src/presets/** gate at 90/75/95/90
• scripts/smoke-stdio.mjs — handshake smoke test (no API keys needed)
• CI flow: npm install → npm run check → npm run build → npm run test:smoke

Registry manifest

server.json at repo root, schema-keyed to https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json. Once published, submit to registry.modelcontextprotocol.io so universal installers like npx add-mcp ai-consensus-mcp pick it up.

Docs

• README "Install in 30 seconds" + Presets reference table
• docs/install.md — long-form install reference (per-host details, Cursor deeplink format, manual fallback)
• CHANGELOG.md initialised

Test plan

• npm run check (typecheck + lint + format:check + test:coverage): 120/120 tests pass; coverage 65.1% global, 96.6% on src/presets/, 85%+ on src/installer/
• npm run build && npm run test:smoke — 6 tools advertised end-to-end
• node dist/index.js install --list-hosts reports detection correctly
• node dist/index.js install --help shows the install help
• node dist/index.js --version returns 0.10.0
• node dist/index.js --config <path> (no subcommand) still routes to serve
• Existing 0.10 server.test.ts assertions updated where the surface changed (the legacy "exactly one tool" assertion now expects 6 — visible in the diff)

Why this is shaped this way

• One tool per preset, plus the existing consensus. Presets need to be discoverable in host autocomplete; a single consensus tool with a preset parameter would be invisible. Generic consensus stays for power users.
• Pure data preset definitions. No runtime side-effects in the definition modules — each preset is a plain object exporting panel, defaults, judgeSystemPrompt, etc. Snapshot tests lock the resolved prompts so a careless edit can't silently change behaviour.
• Adapter takes provider map per call. Preset runs may resolve a participant set the user's raw config doesn't expose verbatim; the adapter signature now takes {providers, providerByParticipant} per-call instead of closing over the full LoadedConfig.
• Installer is merge-only. Every host's config holds far more than just mcpServers. Atomic write + per-key merge protects user state.
• CLI subcommands keep 0.10 invocations identical. serve is the implicit default; --config X (no subcommand, leading flag) still routes to serve so existing host configs work without edits.

Deferred (planned for next minors)

• Tool-calling integration — depends on ai-consensus-core@0.11.0 publishing (see feat: add tool-calling primitives (0.11.0) ai-consensus-core#3). Will add tools.upstreamServers config, MCP composition, executor + redaction, updated presets that bind tools.
• docs/install.html for GitHub Pages with a Cursor one-click button.
• --verify flag to run a smoke test post-install.
• --init-config flag to bootstrap a starter config.
• CI installer matrix that validates produced JSON against host schemas.
• Config-side preset overrides (mergePresets infrastructure in place; no consumer asking yet).

Version policy

package.json.version is left at 0.10.0 in this PR — happy to bump on the same branch, or leave it for the release commit so 0.11.0 lines up with the upstream tool-calling release. Open question for you to call.