Create documentation folder with user-facing guides

[x3ek]

Description

Create a docs/ folder in the repository with user-facing documentation. SquishMark has grown to include many features (themes, Atom feed, featured posts, draft filtering, admin notes, analytics, Pygments syntax highlighting, etc.) but has no structured documentation beyond the developer-focused CLAUDE.md and README.md.

Documentation should be written incrementally — each new feature should include a docs update going forward.

Proposed Structure

docs/
├── README.md                    # Docs index / table of contents
├── getting-started/
│   ├── installation.md          # Clone, install, configure, run
│   ├── quick-start.md           # Create content repo, first post, deploy
│   └── configuration.md         # config.yml reference (all options)
├── content/
│   ├── posts.md                 # Writing posts, frontmatter fields, drafts
│   ├── pages.md                 # Static pages, hidden pages
│   ├── series.md                # Post series (once implemented)
│   ├── frontmatter.md           # Complete frontmatter reference
│   └── static-files.md          # Images, favicon, user static files
├── features/
│   ├── themes.md                # Using themes, switching themes, per-post themes
│   ├── syntax-highlighting.md   # Pygments styles, code blocks, language labels
│   ├── feed.md                  # Atom feed configuration
│   ├── featured-posts.md        # Featured post/page frontmatter
│   ├── reading-time.md          # How reading time is calculated
│   ├── open-graph.md            # OG meta tags, social sharing previews
│   ├── admin.md                 # Admin dashboard, notes, analytics, cache
│   └── draft-filtering.md       # Draft visibility rules
├── themes/
│   ├── creating-themes.md       # Theme authoring guide (from skill)
│   ├── template-reference.md    # All template variables, blocks, filters
│   ├── default-theme.md         # Default theme overview
│   ├── blue-tech-theme.md       # Blue Tech theme overview
│   └── terminal-theme.md        # Terminal theme overview + config options
├── deployment/
│   ├── fly-io.md                # Fly.io deployment guide
│   └── docker.md                # Docker build and run
└── development/
    ├── contributing.md           # Dev setup, running tests, PR guidelines
    └── scripts.md               # Dev scripts reference (start-dev, run-checks, etc.)

Priority

Start with the most impactful docs first:

1. Getting Started — installation, quick-start, configuration
2. Content — posts, pages, frontmatter reference
3. Features — themes, syntax highlighting, feed
4. Deployment — Fly.io, Docker
5. Theme Authoring — for theme creators
6. Development — for contributors

Guidelines

• Write for users, not developers (unless in development/)
• Include examples and code snippets
• Keep each file focused on one topic
• Link between related docs
• Use consistent heading structure
• Document current behavior, not aspirational features

Going Forward

Every new feature PR should include a docs update or a follow-up docs issue. Add a docs label check to the PR template as a reminder.

— Claude