fix: lifecycle methods need value receivers - app detail page 500 (v0.158.1)

Shipped in v0.158.0, caught live within the hour. /apps/<slug> returned 500
for EVERY app: html/template cannot call a pointer-receiver method on a
non-addressable value, and appDetailHandler passes Meta as a VALUE inside a
map[string]interface{}.

It compiled and every test passed because nothing rendered app_info - the
catalog tests used the funcmap route, which takes a value and works either
way. A template method call is only checked when the template runs.

Adds TestAppInfoRendersForEveryLifecycle with the handler's exact data shape.

controller/internal/stacks/metadata.go

@@ -220,7 +220,7 @@ const (
 // or a state added in a later release, silently pull a working app out of every customer's catalog.
 // The gate that actually protects against installing something is `CanInstall`, and it is fed by
 // this same function, so the two can never disagree.
-func (m *Metadata) EffectiveLifecycle() string {
+func (m Metadata) EffectiveLifecycle() string {
 	switch m.Lifecycle {
 	case "", LifecycleAvailable:
 		return LifecycleAvailable
@@ -233,13 +233,20 @@ func (m *Metadata) EffectiveLifecycle() string {
 	}
 }
 
+// VALUE receivers on all three, deliberately: html/template cannot call a POINTER-receiver method
+// on a non-addressable value, and `.Meta` reaches the templates as a stacks.Metadata VALUE inside a
+// map[string]interface{}. With a pointer receiver `{{if .Meta.IsAbandoned}}` fails at RENDER time
+// with "can't evaluate field IsAbandoned in type interface {}" — which is a 500 on the page, not a
+// compile error, so nothing catches it until someone loads the page. That is exactly how it shipped
+// once (v0.158.0, caught live the same hour). Keep these value receivers.
+//
 // CanInstall reports whether this app may be offered/installed. The catalog listing and the deploy
 // endpoint MUST both use this — a template excluded from the list but accepted by a direct POST
 // would be a gate in name only.
-func (m *Metadata) CanInstall() bool { return m.EffectiveLifecycle() == LifecycleAvailable }
+func (m Metadata) CanInstall() bool { return m.EffectiveLifecycle() == LifecycleAvailable }
 
 // IsAbandoned reports whether a DEPLOYED instance should carry the "no longer maintained" notice.
-func (m *Metadata) IsAbandoned() bool { return m.EffectiveLifecycle() == LifecycleAbandoned }
+func (m Metadata) IsAbandoned() bool { return m.EffectiveLifecycle() == LifecycleAbandoned }
 
 // LoadMetadata reads .felhom.yml from a stack directory.
 // Returns default metadata if the file doesn't exist.