refactor(scrape): detect prose-style "must be X" discriminator values on variants

Sealed-interface union variants whose Type/Source field is declared as
bare prose (e.g. "Type of the result, must be article" or "Scope type,
must be all_private_chats") were skipped by extractEnumValues because
the existing patterns require curly-quoted values. The genapi emitter
already extracted these values via discBareRE for marshal-side
discriminator injection; lifting the same detection into the scraper
populates Field.EnumValues so planUnifiedUnionEnums folds them into
shared union-level enums automatically.

Unions newly unified (10): BotCommandScope, MenuButton, InputMedia,
InputPaidMedia, InputPollMedia, InputPollOptionMedia, InputProfilePhoto,
InputStoryContent, InlineQueryResult, PassportElementError.

InputMessageContent stays excluded — its variants dispatch
structurally on field presence and have no Type/Source field, so
planUnifiedUnionEnums correctly skips it.

Constants added: 60 typed enum constants across the 10 unions; the
corresponding variant struct fields are retyped from string to the
shared enum.

Internal call-site cleanups: 0 — no internal package referenced these
discriminator values via magic strings.

False positives the prose detector explicitly rejects: terminal
prose-word continuations like "must be sent", "must be shown above",
"must be specified", "must be paid", "must be active", "must be one
of 3, 6, or 12", "must be between 5 and 100000", "must be a Pay
button", "must be repainted". Guarded via terminal-position regex
anchor + closed-list isProseWord filter.

Determinism verified across two consecutive make regen-from-fixture
runs. go test -race ./..., go vet ./..., staticcheck ./... all clean.

api/enums.gen.go

@@ -21,6 +21,18 @@ const (
 	BackgroundTypeKindChatTheme BackgroundTypeKind = "chat_theme"
 )
 
+type BotCommandScopeType string
+
+const (
+	BotCommandScopeTypeDefault               BotCommandScopeType = "default"
+	BotCommandScopeTypeAllPrivateChats       BotCommandScopeType = "all_private_chats"
+	BotCommandScopeTypeAllGroupChats         BotCommandScopeType = "all_group_chats"
+	BotCommandScopeTypeAllChatAdministrators BotCommandScopeType = "all_chat_administrators"
+	BotCommandScopeTypeChat                  BotCommandScopeType = "chat"
+	BotCommandScopeTypeChatAdministrators    BotCommandScopeType = "chat_administrators"
+	BotCommandScopeTypeChatMember            BotCommandScopeType = "chat_member"
+)
+
 type ChatBoostSourceKind string
 
 const (
@@ -92,6 +104,75 @@ const (
 	InlineQueryResultGifThumbnailMimeTypeVideoOfMp4  InlineQueryResultGifThumbnailMimeType = "video/mp4"
 )
 
+type InlineQueryResultType string
+
+const (
+	InlineQueryResultTypeAudio    InlineQueryResultType = "audio"
+	InlineQueryResultTypeDocument InlineQueryResultType = "document"
+	InlineQueryResultTypeGif      InlineQueryResultType = "gif"
+	InlineQueryResultTypeMpeg4Gif InlineQueryResultType = "mpeg4_gif"
+	InlineQueryResultTypePhoto    InlineQueryResultType = "photo"
+	InlineQueryResultTypeSticker  InlineQueryResultType = "sticker"
+	InlineQueryResultTypeVideo    InlineQueryResultType = "video"
+	InlineQueryResultTypeVoice    InlineQueryResultType = "voice"
+	InlineQueryResultTypeArticle  InlineQueryResultType = "article"
+	InlineQueryResultTypeContact  InlineQueryResultType = "contact"
+	InlineQueryResultTypeGame     InlineQueryResultType = "game"
+	InlineQueryResultTypeLocation InlineQueryResultType = "location"
+	InlineQueryResultTypeVenue    InlineQueryResultType = "venue"
+)
+
+type InputMediaType string
+
+const (
+	InputMediaTypeAnimation InputMediaType = "animation"
+	InputMediaTypeAudio     InputMediaType = "audio"
+	InputMediaTypeDocument  InputMediaType = "document"
+	InputMediaTypeLivePhoto InputMediaType = "live_photo"
+	InputMediaTypePhoto     InputMediaType = "photo"
+	InputMediaTypeVideo     InputMediaType = "video"
+)
+
+type InputPaidMediaType string
+
+const (
+	InputPaidMediaTypeLivePhoto InputPaidMediaType = "live_photo"
+	InputPaidMediaTypePhoto     InputPaidMediaType = "photo"
+	InputPaidMediaTypeVideo     InputPaidMediaType = "video"
+)
+
+type InputPollMediaType string
+
+const (
+	InputPollMediaTypeAnimation InputPollMediaType = "animation"
+	InputPollMediaTypeAudio     InputPollMediaType = "audio"
+	InputPollMediaTypeDocument  InputPollMediaType = "document"
+	InputPollMediaTypeLivePhoto InputPollMediaType = "live_photo"
+	InputPollMediaTypeLocation  InputPollMediaType = "location"
+	InputPollMediaTypePhoto     InputPollMediaType = "photo"
+	InputPollMediaTypeVenue     InputPollMediaType = "venue"
+	InputPollMediaTypeVideo     InputPollMediaType = "video"
+)
+
+type InputPollOptionMediaType string
+
+const (
+	InputPollOptionMediaTypeAnimation InputPollOptionMediaType = "animation"
+	InputPollOptionMediaTypeLivePhoto InputPollOptionMediaType = "live_photo"
+	InputPollOptionMediaTypeLocation  InputPollOptionMediaType = "location"
+	InputPollOptionMediaTypePhoto     InputPollOptionMediaType = "photo"
+	InputPollOptionMediaTypeSticker   InputPollOptionMediaType = "sticker"
+	InputPollOptionMediaTypeVenue     InputPollOptionMediaType = "venue"
+	InputPollOptionMediaTypeVideo     InputPollOptionMediaType = "video"
+)
+
+type InputProfilePhotoType string
+
+const (
+	InputProfilePhotoTypeStatic   InputProfilePhotoType = "static"
+	InputProfilePhotoTypeAnimated InputProfilePhotoType = "animated"
+)
+
 type InputStickerFormat string
 
 const (
@@ -100,6 +181,13 @@ const (
 	InputStickerFormatVideo    InputStickerFormat = "video"
 )
 
+type InputStoryContentType string
+
+const (
+	InputStoryContentTypePhoto InputStoryContentType = "photo"
+	InputStoryContentTypeVideo InputStoryContentType = "video"
+)
+
 type KeyboardButtonStyle string
 
 const (
@@ -117,6 +205,14 @@ const (
 	MaskPositionPointChin     MaskPositionPoint = "chin"
 )
 
+type MenuButtonType string
+
+const (
+	MenuButtonTypeCommands MenuButtonType = "commands"
+	MenuButtonTypeWebApp   MenuButtonType = "web_app"
+	MenuButtonTypeDefault  MenuButtonType = "default"
+)
+
 type MessageEntityType string
 
 const (
@@ -212,6 +308,20 @@ const (
 	PassportElementErrorSelfieTypeInternalPassport PassportElementErrorSelfieType = "internal_passport"
 )
 
+type PassportElementErrorSource string
+
+const (
+	PassportElementErrorSourceData             PassportElementErrorSource = "data"
+	PassportElementErrorSourceFrontSide        PassportElementErrorSource = "front_side"
+	PassportElementErrorSourceReverseSide      PassportElementErrorSource = "reverse_side"
+	PassportElementErrorSourceSelfie           PassportElementErrorSource = "selfie"
+	PassportElementErrorSourceFile             PassportElementErrorSource = "file"
+	PassportElementErrorSourceFiles            PassportElementErrorSource = "files"
+	PassportElementErrorSourceTranslationFile  PassportElementErrorSource = "translation_file"
+	PassportElementErrorSourceTranslationFiles PassportElementErrorSource = "translation_files"
+	PassportElementErrorSourceUnspecified      PassportElementErrorSource = "unspecified"
+)
+
 type PassportElementErrorTranslationFileType string
 
 const (