feat(launcher): initial stable release v0.9.0

Application lifecycle manager enforcing a three-phase init/wire/start sequence with reverse-order graceful shutdown and per-component stop timeouts.

What's included:
- `Component` interface (OnInit / OnStart / OnStop) and `Hook` type for BeforeStart wiring functions
- `Launcher` interface with Append, BeforeStart, Run (blocks on SIGINT/SIGTERM), and idempotent Shutdown(ctx)
- `New(logger, opts...)` constructor with configurable ComponentStopTimeout (default 15 s); no global state

Tested-via: todo-api POC integration
Reviewed-against: docs/adr/

compliance_test.go

@@ -0,0 +1,9 @@
+package launcher_test
+
+import (
+	"code.nochebuena.dev/go/launcher"
+	"code.nochebuena.dev/go/logz"
+)
+
+// Verify New returns a Launcher.
+var _ launcher.Launcher = launcher.New(logz.New(logz.Options{}))