refactor(root): move root artefacts to their canonical locations

.github/CONTRIBUTING.md

@@ -0,0 +1,182 @@
+# Contributing to PanLL
+
+## Why These Tools?
+
+Before you dive in, it helps to understand *why* PanLL uses the stack it
+does. These aren’t arbitrary preferences — they’re lessons learned from
+building a 14-panel stateful application.
+
+**AffineScript instead of TypeScript** — PanLL has 26,000+ lines of
+state management across 14 panels. TypeScript’s structural type system
+means `any` leaks are always one cast away, and discriminated unions
+require manual type guards that are easy to forget. ReScript’s sound
+type system means if it compiles, the types are correct — no escape
+hatches, no `as` `unknown` `as`, no runtime type errors. Exhaustive
+pattern matching on variant types caught dozens of “missing case” bugs
+during the panel expansion. See
+<a href="https://rescript-lang.org" class="org">rescript-lang</a>.
+
+**Rust + Gossamer instead of Electron** — PanLL’s release binary is ~5
+MB. An equivalent Electron app would be 100+ MB (shipping an entire
+Chromium). The Rust backend runs through Gossamer (Zig + WebKitGTK), a
+lightweight container-friendly webview shell. Filesystem watching, git
+blame parsing, and HTTP clients run with no garbage collector pauses —
+important when 106 panels are subscribed to live events. PanLL
+originally used Tauri 2.0 but migrated to Gossamer for better container
+support and tighter integration with the hyperpolymath stack.
+
+**Deno instead of npm/Node** — No `node_modules` directory (1,200\
+transitive deps for a typical Node project). Built-in test runner.
+Secure-by-default permissions. ReScript and Tailwind run via `npm:`
+specifiers in `deno.json`; there is no `package.json` and no npm CLI is
+invoked.
+
+**Elixir/BEAM for middleware** — BEAM’s supervision trees mean a
+crashing backend connection restarts itself without taking down the
+whole panel surface. Pattern matching on messages is the same philosophy
+as ReScript’s TEA on the frontend.
+
+**Julia for data processing** — When batch analysis needs actual numeric
+performance. Python’s GIL means “import numpy and pray”; Julia’s
+multiple dispatch compiles to LLVM native code for every combination of
+argument types.
+
+If you’re coming from TypeScript/React, the biggest mental shift is TEA
+(The Elm Architecture): state changes are pure functions, side effects
+are commands, and the compiler enforces exhaustiveness everywhere. It’s
+more explicit than hooks, but after the first day you’ll wonder why you
+ever tolerated `useEffect`.
+
+’’’’’
+
+## Getting Started
+
+``` bash
+# Clone the repository
+git clone https://github.com/hyperpolymath/panll.git
+cd panll
+
+# Using Nix (recommended for reproducibility)
+nix develop
+
+# Or using toolbox/distrobox
+toolbox create panll-dev
+toolbox enter panll-dev
+# Install dependencies manually
+
+# Verify setup
+just check   # or: cargo check / mix compile / etc.
+just test    # Run test suite
+```
+
+### Repository Structure
+
+    panll/
+    ├── src/                 # Source code (Perimeter 1-2)
+    ├── lib/                 # Library code (Perimeter 1-2)
+    ├── extensions/          # Extensions (Perimeter 2)
+    ├── plugins/             # Plugins (Perimeter 2)
+    ├── tools/               # Tooling (Perimeter 2)
+    ├── docs/                # Documentation (Perimeter 3)
+    │   ├── architecture/    # ADRs, specs (Perimeter 2)
+    │   └── proposals/       # RFCs (Perimeter 3)
+    ├── examples/            # Examples (Perimeter 3)
+    ├── spec/                # Spec tests (Perimeter 3)
+    ├── tests/               # Test suite (Perimeter 2-3)
+    ├── .well-known/         # Protocol files (Perimeter 1-3)
+    ├── .github/             # GitHub config (Perimeter 1)
+    │   ├── ISSUE_TEMPLATE/
+    │   └── workflows/
+    ├── CHANGELOG.md
+    ├── CODE_OF_CONDUCT.md
+    ├── CONTRIBUTING.md      # This file
+    ├── GOVERNANCE.md
+    ├── LICENSE
+    ├── MAINTAINERS.md
+    ├── README.adoc
+    ├── SECURITY.md
+    ├── flake.nix            # Nix flake (Perimeter 1)
+    └── Justfile             # Task runner (Perimeter 1)
+
+’’’’’
+
+## How to Contribute
+
+### Reporting Bugs
+
+**Before reporting**: 1. Search existing issues 2. Check if it’s already
+fixed in `main` 3. Determine which perimeter the bug affects
+
+**When reporting**:
+
+Use the [bug report template](.github/ISSUE_TEMPLATE/bug_report.md) and
+include:
+
+- Clear, descriptive title
+
+- Environment details (OS, versions, toolchain)
+
+- Steps to reproduce
+
+- Expected vs actual behaviour
+
+- Logs, screenshots, or minimal reproduction
+
+### Suggesting Features
+
+**Before suggesting**: 1. Check the [roadmap](ROADMAP.md) if available
+2. Search existing issues and discussions 3. Consider which perimeter
+the feature belongs to
+
+**When suggesting**:
+
+Use the [feature request
+template](.github/ISSUE_TEMPLATE/feature_request.md) and include:
+
+- Problem statement (what pain point does this solve?)
+
+- Proposed solution
+
+- Alternatives considered
+
+- Which perimeter this affects
+
+### Your First Contribution
+
+Look for issues labelled:
+
+- [`good` `first`
+  `issue`](https://github.com/hyperpolymath/panll/labels/good%20first%20issue)
+  — Simple Perimeter 3 tasks
+
+- [`help`
+  `wanted`](https://github.com/hyperpolymath/panll/labels/help%20wanted)
+  — Community help needed
+
+- [`documentation`](https://github.com/hyperpolymath/panll/labels/documentation)
+  — Docs improvements
+
+- [`perimeter-3`](https://github.com/hyperpolymath/panll/labels/perimeter-3)
+  — Community sandbox scope
+
+’’’’’
+
+## Development Workflow
+
+### Branch Naming
+
+    docs/short-description       # Documentation (P3)
+    test/what-added              # Test additions (P3)
+    feat/short-description       # New features (P2)
+    fix/issue-number-description # Bug fixes (P2)
+    refactor/what-changed        # Code improvements (P2)
+    security/what-fixed          # Security fixes (P1-2)
+
+### Commit Messages
+
+We follow [Conventional Commits](https://www.conventionalcommits.org/):
+\`\`\` ():
+
+\[optional body\]
+
+\[optional footer\]

panel-clades/.envrc

@@ -7,8 +7,8 @@ if has asdf; then
   use asdf
 fi
 
-# Load Guix shell if guix.scm exists
-if has guix && [ -f guix.scm ]; then
+# Load Guix shell if build/guix.scm exists
+if has guix && [ -f build/guix.scm ]; then
   use guix
 fi