Initial HerbAPI implementation

Rust/Axum REST API (herbapi-api) with PostgreSQL, S3/Garage, OIDC auth.
Dioxus 0.7 WASM frontend (herbapi-ui) with sidebar layout and botanical reference style.
9 SQL migrations covering families, species, cultivars, suppliers, companions, images, users, API tokens.

herbapi-api/migrations/009_create_api_tokens.sql

@@ -0,0 +1,8 @@
+CREATE TABLE IF NOT EXISTS api_tokens (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    name TEXT NOT NULL,
+    token_hash TEXT NOT NULL UNIQUE,
+    scopes TEXT[] NOT NULL DEFAULT '{}',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    last_used_at TIMESTAMPTZ
+);