Initial iris repository structure

WASM reactive UI framework for Go:
- reactive/ - Signal[T], Effect, Runtime
- ui/ - Button, Text, Input, View, Canvas, SVG components
- navigation/ - Router, guards, history management
- auth/ - OIDC client for WASM applications
- host/ - Static file server

Extracted from arcadia as open-source component.

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

CLAUDE.md

@@ -0,0 +1,101 @@
+# Iris
+
+WASM reactive UI framework for Go.
+
+## Organization Context
+
+This repo is part of Flowmade. See:
+- [Organization manifesto](../architecture/manifesto.md) - who we are, what we believe
+- [Repository map](../architecture/repos.md) - how this fits in the bigger picture
+- [Vision](./vision.md) - what this specific product does
+
+## Setup
+
+```bash
+git clone git@git.flowmade.one:flowmade-one/iris.git
+cd iris
+```
+
+## Project Structure
+
+```
+iris/
+├── reactive/      # Signal[T], Effect, Runtime - core reactivity
+├── ui/            # Components: Button, Text, Input, View, Canvas, SVG
+├── navigation/    # Router, guards, history management
+├── auth/          # OIDC client for WASM applications
+├── host/          # Static file server for WASM apps
+└── internal/      # Internal element abstraction
+```
+
+## Development
+
+```bash
+# Build (WASM target)
+GOOS=js GOARCH=wasm go build ./...
+
+# Build host server (native)
+go build ./host/...
+
+# Test
+go test ./...
+
+# Lint
+golangci-lint run
+```
+
+## Architecture
+
+### Reactivity Model
+
+Iris uses a signals-based reactivity model:
+
+```go
+// Create a signal
+count := reactive.NewSignal(0)
+
+// Read value
+fmt.Println(count.Get())
+
+// Update value - triggers dependent effects
+count.Set(count.Get() + 1)
+
+// Create derived state
+doubled := reactive.Computed(func() int {
+    return count.Get() * 2
+})
+```
+
+### Components
+
+All UI components implement a common interface and render to DOM elements:
+
+```go
+// Create a button
+btn := ui.Button("Click me", func() {
+    count.Set(count.Get() + 1)
+})
+
+// Create reactive text
+text := ui.Text(func() string {
+    return fmt.Sprintf("Count: %d", count.Get())
+})
+```
+
+### Routing
+
+Client-side routing with guards:
+
+```go
+router := navigation.NewRouter()
+router.Route("/", homeView)
+router.Route("/users/:id", userView)
+router.Guard("/admin/*", authGuard)
+```
+
+## Key Patterns
+
+- **No virtual DOM** - Direct DOM manipulation via syscall/js
+- **Signals propagate** - Changes flow through the dependency graph
+- **Components are functions** - Return DOM elements, not component instances
+- **WASM-only UI code** - Use build tags for browser-specific code