docs: add dual-instance planning pattern (Jon Williams)

Add vertical separation pattern (planner/implementer) as complement to horizontal scaling (Boris pattern).

## Changes

**Main guide (ultimate-guide.md)**:
- New Section 9.17.1: "Alternative Pattern: Dual-Instance Planning" (~350 lines)
  - When to use (solo devs, spec-heavy, $100-200/month)
  - Setup instructions (2 Claude instances, Plans/ directory)
  - Complete workflow (5 phases: planning, review, implementation, verification, archive)
  - Comparison table (Boris horizontal vs Jon vertical scaling)
  - Cost analysis (2 instances vs correction loops)
  - Agent-ready plan best practices
  - Limitations and tips

**Workflow file (workflows/dual-instance-planning.md)**:
- Full workflow guide (~750 lines)
- Complete example (JWT auth implementation)
- Plan template (ready to copy-paste)
- Cost breakdown and decision matrix
- Troubleshooting and bash aliases

**References updated**:
- machine-readable/reference.yaml: 15 new entries
  - dual_instance_planning, dual_instance_workflow, etc.
  - Line numbers, source attribution, metadata
- guide/workflows/plan-driven.md: Link in See Also section
- README.md: Update evaluation count (46 → 47)

**Evaluation documented**:
- docs/resource-evaluations/jon-williams-dual-instance-pattern.md
  - Full methodology (fetch, analyze, challenge, fact-check)
  - Score progression (2-3/5 → 4/5 after technical-writer challenge)
  - Gap analysis, comparison, integration rationale

## Source
LinkedIn post by Jon Williams (Product Designer, UK)
Date: 2026-02-03
URL: https://www.linkedin.com/posts/thatjonwilliams_ive-been-using-cursor-for-six-months-now-activity-7424481861802033153-k8bu

Context: Transition from Cursor (6 months) to Claude Code with Opus 4.5
Pattern: Vertical separation (Claude Zero: planning/review, Claude One: implementation)
Distinction: Orthogonal to Boris pattern (vertical vs horizontal scaling)

## Stats
- Lines added: ~1,400
- Files modified: 4
- Files created: 2 (workflow + evaluation)
- References added: 15 (reference.yaml)
- Evaluation score: 4/5 (High Value)
- Integration time: ~2.5 hours

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

README.md

@@ -15,7 +15,7 @@
   <a href="https://zread.ai/FlorianBruniaux/claude-code-ultimate-guide"><img src="https://img.shields.io/badge/Ask_Zread-_.svg?style=flat&color=00b0aa&labelColor=000000&logo=data%3Aimage%2Fsvg%2Bxml%3Bbase64%2CPHN2ZyB3aWR0aD0iMTYiIGhlaWdodD0iMTYiIHZpZXdCb3g9IjAgMCAxNiAxNiIgZmlsbD0ibm9uZSIgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIj4KPHBhdGggZD0iTTQuOTYxNTYgMS42MDAxSDIuMjQxNTZDMS44ODgxIDEuNjAwMSAxLjYwMTU2IDEuODg2NjQgMS42MDE1NiAyLjI0MDFWNC45NjAxQzEuNjAxNTYgNS4zMTM1NiAxLjg4ODEgNS42MDAxIDIuMjQxNTYgNS42MDAxSDQuOTYxNTZDNS4zMTUwMiA1LjYwMDEgNS42MDE1NiA1LjMxMzU2IDUuNjAxNTYgNC45NjAxVjIuMjQwMUM1LjYwMTU2IDEuODg2NjQgNS4zMTUwMiAxLjYwMDEgNC45NjE1NiAxLjYwMDFaIiBmaWxsPSIjZmZmIi8%2BCjxwYXRoIGQ9Ik00Ljk2MTU2IDEwLjM5OTlIMi4yNDE1NkMxLjg4ODEgMTAuMzk5OSAxLjYwMTU2IDEwLjY4NjQgMS42MDE1NiAxMS4wMzk5VjEzLjc1OTlDMS42MDE1NiAxNC4xMTM0IDEuODg4MSAxNC4zOTk5IDIuMjQxNTYgMTQuMzk5OUg0Ljk2MTU2QzUuMzE1MDIgMTQuMzk5OSA1LjYwMTU2IDE0LjExMzQgNS42MDE1NiAxMy43NTk5VjExLjAzOTlDNS42MDE1NiAxMC42ODY0IDUuMzE1MDIgMTAuMzk5OSA0Ljk2MTU2IDEwLjM5OTlaIiBmaWxsPSIjZmZmIi8%2BCjxwYXRoIGQ9Ik0xMy43NTg0IDEuNjAwMUgxMS4wMzg0QzEwLjY4NSAxLjYwMDEgMTAuMzk4NCAxLjg4NjY0IDEwLjM5ODQgMi4yNDAxVjQuOTYwMUMxMC4zOTg0IDUuMzEzNTYgMTAuNjg1IDUuNjAwMSAxMS4wMzg0IDUuNjAwMUgxMy43NTg0QzE0LjExMTkgNS42MDAxIDE0LjM5ODQgNS4zMTM1NiAxNC4zOTg0IDQuOTYwMVYyLjI0MDFDMTQuMzk4NCAxLjg4NjY0IDE0LjExMTkgMS42MDAxIDEzLjc1ODQgMS42MDAxWiIgZmlsbD0iI2ZmZiIvPgo8cGF0aCBkPSJNNCAxMkwxMiA0TDQgMTJaIiBmaWxsPSIjZmZmIi8%2BCjxwYXRoIGQ9Ik00IDEyTDEyIDQiIHN0cm9rZT0iI2ZmZiIgc3Ryb2tlLXdpZHRoPSIxLjUiIHN0cm9rZS1saW5lY2FwPSJyb3VuZCIvPgo8L3N2Zz4K&logoColor=ffffff" alt="Ask Zread"/></a>
 </p>
 
-> **Claude Code (Anthropic): the learning curve, solved.** ~16K-line guide + 103 templates + 257 quiz questions + 22 event hooks + 46 resource evaluations. Beginner → Power User.
+> **Claude Code (Anthropic): the learning curve, solved.** ~16K-line guide + 103 templates + 257 quiz questions + 22 event hooks + 47 resource evaluations. Beginner → Power User.
 
 ---
 
@@ -161,7 +161,7 @@ Educational templates with explanations:
 
 [Browse Catalog →](./examples/)
 
-### 🔍 45 Resource Evaluations
+### 🔍 47 Resource Evaluations
 
 Systematic assessment of external resources (5-point scoring):
 - Articles, videos, tools, frameworks
@@ -425,7 +425,7 @@ cd quiz && npm install && npm start
 </details>
 
 <details>
-<summary><strong>Resource Evaluations</strong> (44 assessments)</summary>
+<summary><strong>Resource Evaluations</strong> (47 assessments)</summary>
 
 Systematic evaluation of external resources (tools, methodologies, articles) before integration into the guide.