fix(parser): align Go and JS parsers with capture grammar spec

Kind prefixes now follow the canonical grammar: `-` for todo,
`@time` for event, `!time` for reminder. Removed `*`/`◇`/`▸`
as capture aliases (display-layer only). Added `\` escape prefix,
`?` query mode, `!pin` flag extraction, `##word` hash escape,
and tag lowercasing. Both parsers produce identical results.

internal/api/entities.go

@@ -16,6 +16,7 @@ type CreateEntityRequest struct {
 	Glyph       *string  `json:"glyph"`
 	TimeAnchor  *string  `json:"time_anchor"`
 	Tags        []string `json:"tags"`
+	Pinned      *bool    `json:"pinned"`
 	CardType    *string  `json:"card_type"`
 	CardData    *string  `json:"card_data"`
 }
@@ -145,6 +146,9 @@ func createEntity(store *db.Store) http.HandlerFunc {
 			TimeAnchor:  req.TimeAnchor,
 			Tags:        req.Tags,
 		}
+		if req.Pinned != nil && *req.Pinned {
+			e.Pinned = true
+		}
 
 		if req.CardType != nil {
 			if !db.ValidCardType(*req.CardType) {