feat(ultraplan-local): v1.6.0 — /ultraresearch-local deep research command

Add /ultraresearch-local for structured research combining local codebase
analysis with external knowledge via parallel agent swarms. Produces research
briefs with triangulation, confidence ratings, and source quality assessment.

New command: /ultraresearch-local with modes --quick, --local, --external, --fg.
New agents: research-orchestrator (opus), docs-researcher, community-researcher,
security-researcher, contrarian-researcher, gemini-bridge (all sonnet).
New template: research-brief-template.md.

Integration: --research flag in /ultraplan-local accepts pre-built research
briefs (up to 3), enriches the interview and exploration phases. Planning
orchestrator cross-references brief findings during synthesis.

Design principle: Context Engineering — right information to right agent at
right time. Research briefs are structured artifacts in the pipeline:
ultraresearch → brief → ultraplan --research → plan → ultraexecute.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CONTRIBUTING.md

@@ -0,0 +1,43 @@
+# Contributing to linkedin-thought-leadership
+
+This is a solo project. Bug reports and feature requests are welcome, but pull requests are not accepted.
+
+## Reporting bugs
+
+Open an issue with:
+- Plugin version (from `.claude-plugin/plugin.json`)
+- Claude Code version (`claude --version`)
+- What you did, what you expected, what happened instead
+- Whether it fails consistently or occasionally
+
+## Suggesting features or improvements
+
+Open an issue describing:
+- The problem you ran into
+- What you think would solve it
+- Any alternatives you considered
+
+## Design principles
+
+Changes to this plugin must preserve:
+- **Cross-platform** — all hooks are Node.js (.mjs), no bash dependency
+- **Privacy-first** — personal data (voice samples, analytics, queue) stays gitignored
+- **Generalizable** — no hardcoded user identity; templates for personalization
+- **Cost-aware** — Sonnet for most agents, Haiku for lightweight tasks
+- **Algorithm-grounded** — content strategies backed by documented LinkedIn signals
+
+## Testing locally
+
+```bash
+claude plugin add /path/to/linkedin-thought-leadership
+
+# In a Claude Code session:
+/linkedin           # Check status and command menu
+/linkedin:quick     # Test quick post flow
+/linkedin:profile   # Test profile audit
+```
+
+For analytics:
+```bash
+cd scripts/analytics && npm install && npm test
+```