feat(watcher): Placer interface; acceptance tests for the sprint goal (#209)

A clip dropped in raw/ with no other action lands in web-clip, its entity and
concept are the shared pages, raw/ is empty and nothing waits for a human;
client-marked text and a typo'd wing name park; a deliberate subfolder places.
Real pipeline and file layout, model stubbed.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

ingestion/internal/watcher/watcher.go

@@ -31,10 +31,12 @@ type Config struct {
 	// memory (hyperguild#198). 0 means defaultMaxNoteBytes.
 	MaxNoteBytes int64
 
-	// Resolver, when set, decides each note's wing (hyperguild#205): explicit
-	// subfolder/frontmatter, else classifier + scorer. A note it cannot place
-	// is parked in raw/needs-review/ for a human. Nil keeps the retired layout.
-	Resolver *wing.Resolver
+	// Resolver, when set, decides each note's wing (hyperguild#205, #208): a
+	// deliberate subfolder/frontmatter wing, else the default wing. A note it
+	// cannot place is parked in raw/needs-review/ for a human. Nil keeps the
+	// retired layout. Set it only to a non-nil value: a nil pointer inside the
+	// interface is not nil.
+	Resolver wing.Placer
 }
 
 // defaultMaxNoteBytes bounds a single note: extraction and the archive copy both