Document application-owned alias contracts

docs/consumers/guide.md

@@ -1,9 +1,11 @@
 # Consumer guide
 
 CommandKit is distributed as three Go modules. Start with the core and add an
-integration module only when the application uses that library. Each module
-returns core `commandkit.Command` declarations, which the application installs
-through `commandkit.New` or `App.Register`.
+integration module only when the application uses that library. Core and
+integration command factories return canonical `commandkit.Command` values.
+Applications may install those alongside application-owned `RoutingRule`
+declarations through `commandkit.New` or `App.Register`; routing rules are
+installed at the application root, not as group children.
 
 ## Module selection
 
@@ -83,6 +85,45 @@ values convert before input construction. A command's `NewInput` creates input
 only when execution reaches it; help does not construct caller input or run
 provider callbacks.
 
+## Application-owned aliases
+
+Pass commands and aliases together as declarations. Integration factories can
+be called directly in the installation list, and command-scoped flag aliases
+name the canonical command path:
+
+```go
+app, err := commandkit.New(
+	identity,
+	ckprompt.Command(suite),
+	commandkit.Alias("pk", "promptkit"),
+	commandkit.FlagAliasFor("promptkit show prompt", "--fmt", "--format"),
+)
+```
+
+For a reusable collection, use `[]commandkit.Declaration`. Go does not expand a
+`[]commandkit.Command` into `...commandkit.Declaration`, so convert command-only
+slices when composing them with routing rules:
+
+```go
+commands := []commandkit.Command{ckprompt.Command(suite)}
+declarations := make([]commandkit.Declaration, 0, len(commands)+1)
+for _, command := range commands {
+	declarations = append(declarations, command)
+}
+declarations = append(declarations, commandkit.Alias("pk", "promptkit"))
+app, err := commandkit.New(identity, declarations...)
+```
+
+New and Register validate each supplied batch before publishing its commands
+and routing rules. Factories capture their inputs eagerly; malformed or
+conflicting rules are reported at installation. Identical rules are safe to
+contribute from reusable helpers. The [core example](../../examples/core) and
+[composed consumer](../../integrations/ckprompt/examples/composed) show complete
+maintained wiring with ordinary command behavior alongside aliases. The
+[application-owned aliases roadmap](../roadmap/aliases.md) records the routing
+contract; the [CLI reference](../cli.md#application-owned-aliases) describes
+operator-visible behavior.
+
 ## ConfigKit scopes
 
 For an application with one ordinary app configuration loader,