feat: initial project setup with roadmap, exercise data, and docs

Establish SneakySwole project foundation:
- CLAUDE.md with project overview, stack, and development guidelines
- 5-phase roadmap (scaffold, data layer, workout UI, logging, progression)
- Exercise library YAML with 6 warmups and 20 exercises (form cues, tempo, sets)
- User programs YAML with week 1/4 targets for Phillip and Daughter
- Design doc capturing roadmap, data, and auth model decisions
- Code guidelines, security standards, and .gitignore
- Source workout spreadsheet (workout_plan_v2.xlsx)

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

docs/CLAUDE.md

@@ -0,0 +1,22 @@
+# Documentation Folder
+
+This folder contains business planning, architecture decisions, and documentation.
+
+**No application code belongs here.**
+
+## Contents
+
+| Document | Purpose |
+|----------|---------|
+| `code_guidelines.md` | Code creation guidelines and Git strategy |
+| `security.md` | Python focused security code suggestions |
+| `roadmap.md` | 5-phase development roadmap |
+| `plans/` | Design documents and implementation plans |
+
+
+## Guidelines
+
+- Keep documents focused and concise
+- Update docs when architecture decisions change
+- Use markdown tables for structured information
+- Include links to external documentation where relevant