fix: copy-on-wrap commands and typed errors

Clone commands before wrapping Before hooks, export ErrLifecycleNotInContext
and ErrNoDependencies, add Run helper, split command.go and deps.go.

Co-authored-by: Cursor <cursoragent@cursor.com>

README.md

@@ -1,3 +1,49 @@
 # appcli
 
-appcli provides boilerplate dependency handling for command line apps based on [urfave/cli](https://github.com/urfave/cli) that utilize [app](https://gitea.auvem.com/go-toolkit/app).
+Bridge between [urfave/cli/v3](https://github.com/urfave/cli/v3) and [app](https://gitea.auvem.com/go-toolkit/app) lifecycles.
+
+## Install
+
+```bash
+go get gitea.auvem.com/go-toolkit/appcli
+```
+
+## Example
+
+```go
+func main() {
+    lc := app.NewLifecycle()
+    defer lc.Teardown()
+
+    root := appcli.NewRootCommand(&cli.Command{
+        Name:  "myapp",
+        Usage: "My application",
+        Commands: []*cli.Command{
+            appcli.NewCommand(&cli.Command{
+                Name:  "serve",
+                Usage: "Run the server",
+                Action: func(ctx context.Context, c *cli.Command) error {
+                    // modules already loaded via DepFn
+                    return nil
+                },
+            }, func(l *app.Lifecycle, c *cli.Command) ([]*app.Module, error) {
+                return []*app.Module{myModule}, nil
+            }),
+        },
+    })
+
+    if err := appcli.Run(context.Background(), lc, root, os.Args); err != nil {
+        log.Fatal(err)
+    }
+}
+```
+
+## NewRootCommand vs NewCommand
+
+- `NewRootCommand` adds global `--verbose` / `-v` (unless already defined)
+- Both wrap `Before` to call `lifecycle.Require` with modules from `DepFn`
+- Wrapped commands are copied; the original `*cli.Command` is not mutated
+
+## DepFn
+
+The `*cli.Command` argument is the command whose `Before` hook is running. For nested commands, parent hooks receive the parent command; use `VerboseFromCommand` to read root flags from subcommands.