Scaffold GitManager multi-repo dashboard

Runnable skeleton per AGENT.md: Echo server (/, /help, /healthz, /api/repos), read-only repo scanner with in-memory index, the internal/git boundary, the <repo-list> web component with design tokens, and dev tooling (Dockerfile, docker-compose, air, .env.example).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.air.toml

@@ -0,0 +1,20 @@
+# Hot reload for the dev container (AGENT.md §2). Static assets under web/static
+# and components/ are served live from disk, so they need no rebuild; only Go
+# and template (.html) changes trigger a rebuild + restart.
+
+root = "."
+tmp_dir = "tmp"
+
+[build]
+  cmd = "go build -o ./tmp/gitmanager ./cmd/server"
+  bin = "./tmp/gitmanager"
+  include_ext = ["go", "html"]
+  exclude_dir = ["tmp", "bin", ".git", "repos"]
+  delay = 500
+  stop_on_error = true
+
+[log]
+  time = true
+
+[misc]
+  clean_on_exit = true