fix(api,watcher): name the queue, list parked non-markdown, reserved wings, top-level-only frontmatter key; document the inbox (review of #211)

- brain_promote/brain_reject take an optional queue (inbox | needs-review); a
  name present in both is refused instead of silently acting on the top-level
  note; brain_pending labels every entry with its queue
- parked pdf/txt files are listed (they were invisible); only markdown can be
  promoted, the others are moved or rejected
- promote refuses sources/concepts/entities/wiki as a wing
- frontmatterWing reads only a top-level key inside a properly fenced block
- docs/raw-inbox.md: the contract, the three env vars, the known limits
Each behaviour has a test that fails without it (mutation-checked).

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

ingestion/internal/mcp/handlers.go

@@ -94,6 +94,7 @@ func (s *Server) tools() []map[string]any {
 				"wing":     str("target wing, e.g. jepa-fx"),
 				"hall":     enum("target hall", halls...),
 				"slug":     str("optional target slug; defaults to filename minus date prefix"),
+				"queue":    enum("which brain_pending listing the note is in; required only when the name exists in both", "inbox", "needs-review"),
 			}),
 		},
 		{
@@ -102,6 +103,7 @@ func (s *Server) tools() []map[string]any {
 			"inputSchema": schema([]string{"filename"}, map[string]any{
 				"filename": str("basename in brain/raw/, e.g. 2026-04-23-fed-sentiment-scrape.md"),
 				"reason":   str("optional; why this isn't worth promoting"),
+				"queue":    enum("which brain_pending listing the note is in; required only when the name exists in both", "inbox", "needs-review"),
 			}),
 		},
 		noteToolDescriptors()[0],
@@ -383,6 +385,7 @@ type brainPromoteArgs struct {
 	Wing     string `json:"wing"`
 	Hall     string `json:"hall"`
 	Slug     string `json:"slug,omitempty"`
+	Queue    string `json:"queue,omitempty"`
 }
 
 // brainPromote moves a raw/ note into the structured wiki (frontmatter
@@ -395,7 +398,7 @@ func (s *Server) brainPromote(ctx context.Context, args json.RawMessage) (json.R
 	}
 	origin, writtenBy := provenanceFrom(ctx)
 	relPath, err := api.PromoteNote(s.brainDir, api.PromoteOptions{
-		Filename: a.Filename, Wing: a.Wing, Hall: a.Hall, Slug: a.Slug,
+		Filename: a.Filename, Wing: a.Wing, Hall: a.Hall, Slug: a.Slug, Queue: a.Queue,
 		Origin: origin, WrittenBy: writtenBy,
 	})
 	if err != nil {
@@ -408,6 +411,7 @@ func (s *Server) brainPromote(ctx context.Context, args json.RawMessage) (json.R
 type brainRejectArgs struct {
 	Filename string `json:"filename"`
 	Reason   string `json:"reason,omitempty"`
+	Queue    string `json:"queue,omitempty"`
 }
 
 // brainReject records a decision not to promote a raw/ note (api.RejectNote:
@@ -418,7 +422,7 @@ func (s *Server) brainReject(_ context.Context, args json.RawMessage) (json.RawM
 	if err := json.Unmarshal(args, &a); err != nil {
 		return nil, fmt.Errorf("parse args: %w", err)
 	}
-	relPath, err := api.RejectNote(s.brainDir, api.RejectOptions{Filename: a.Filename, Reason: a.Reason})
+	relPath, err := api.RejectNote(s.brainDir, api.RejectOptions{Filename: a.Filename, Reason: a.Reason, Queue: a.Queue})
 	if err != nil {
 		return nil, err
 	}