build(deps): bump github.com/slack-go/slack from 0.20.0 to 0.23.1

[dependabot]

Bumps github.com/slack-go/slack from 0.20.0 to 0.23.1.

Release notes

Sourced from github.com/slack-go/slack's releases.

v0.23.1

[!IMPORTANT] Even though this is a [security] patch release, if you were using an empty secret, this is a breaking change due to a change in behaviour. That's on purpose, to ensure you fix your approach so that there are no footguns.

Fixed

• NewSecretsVerifier now rejects empty signing secrets to avoid accepting forged request signatures when applications are misconfigured.

Full Changelog: slack-go/slack@v0.23.0...v0.23.1

v0.23.0

Added

• feat(socketmode): expose socketmode handler dispatcher method by @​nlopes in slack-go/slack#1550
• feat(block): add card and carousel blocks by @​nlopes in slack-go/slack#1551
• feat(assistant): add username and icon to status update by @​charleenwang in slack-go/slack#1553
• feat(block): add alert block by @​nlopes in slack-go/slack#1552

New Contributors

• @​charleenwang made their first contribution in slack-go/slack#1553

Full Changelog: slack-go/slack@v0.22.0...v0.23.0

v0.22.0

What's Changed

Added

• OAuth PKCE support - OAuthOptionCodeVerifier option for GetOAuthV2Response, plus GenerateCodeVerifier() and GenerateCodeChallenge() helpers (RFC 7636). client_secret is now conditionally omitted when empty in both GetOAuthV2ResponseContext and RefreshOAuthV2TokenContext.
• Manifest scope fields - BotOptional and UserOptional on OAuthScopes.
• Rich text styles - Underline, Highlight, ClientHighlight, and Unlink on RichTextSectionTextStyle. Style field on RichTextSectionUserGroupElement.
• Assistant search context - Sort, SortDir, Before, After, Highlight, IncludeContextMessages, IncludeDeletedUsers, IncludeMessageBlocks, IncludeArchivedChannels, DisableSemanticSearch, Modifiers, TermClauses parameters and new response types (AssistantSearchContextFile, AssistantSearchContextChannel, AssistantSearchContextMessageContext).

Fixed

• socketmode: malformed JSON no longer forces reconnect - json.SyntaxError and json.UnmarshalTypeError now emit an EventTypeIncomingError event and continue reading instead of killing the WebSocket connection.
• socketmode: debug_reconnects query param applied correctly - the parameter was silently discarded due to a missing url.RawQuery assignment.
• ChannelTypes and ContentTypes now send comma-separated values instead of repeated form keys, matching the convention used by every other method in the library.

Docs

• assistant:write scope marked as deprecated in favour of chat:write.

Full Changelog: v0.21.1...v0.22.0

v0.21.1

Added

• MessageEvent channel type helpers — New ChannelTypeChannel, ChannelTypeGroup,

... (truncated)

Changelog

Sourced from github.com/slack-go/slack's changelog.

[0.23.1] - 2026-05-10

Fixed

• NewSecretsVerifier now rejects empty signing secrets to avoid accepting forged request signatures when applications are misconfigured.

[0.23.0] - 2026-04-22

Added

• Block Kit: CardBlock and CarouselBlock — Support for two of the new agent-UI blocks announced in the April 16 Slack changelog. CardBlock is constructed via NewCardBlock with a functional-options pattern and fluent With* builders (WithTitle, WithSubtitle, WithBody, WithIcon, WithHeroImage, WithActions). CarouselBlock is constructed via NewCarouselBlock with a variadic *CardBlock list plus WithBlockID and AddCard helpers. Both blocks wire into Blocks.UnmarshalJSON for round-trip fidelity, and reuse existing ImageBlockElement / ButtonBlockElement / BlockElements types rather than introducing new composition objects.
• Block Kit: AlertBlock — Support for the third of the new agent-UI blocks from the April 16 Slack changelog. AlertBlock is constructed via NewAlertBlock with a *TextBlockObject body and a functional-options pattern. Severity is set via AlertBlockOptionLevel (AlertLevelDefault, AlertLevelInfo, AlertLevelWarning, AlertLevelError, AlertLevelSuccess) and the block ID via AlertBlockOptionBlockID. Wires into Blocks.UnmarshalJSON for round-trip fidelity. Must be delivered via the streaming chunks API — chat.postMessage rejects it as an unsupported block type.
• Streaming-message chunks API — chat.startStream / chat.appendStream / chat.stopStream now accept a chunks parameter. Added MsgOptionChunks along with a StreamChunk interface and four chunk types: MarkdownTextChunk, TaskUpdateChunk, PlanUpdateChunk, and BlocksChunk (each with a New*Chunk constructor). This is the supported transport for streaming Block Kit content and the new agent-UI blocks in particular (which chat.postMessage rejects as Unsupported block type).
• MsgOptionTaskDisplayMode — New option for chat.startStream controlling whether task chunks render as a sequential timeline or a grouped plan. Accepts TaskDisplayModeTimeline or TaskDisplayModePlan.
• Added Username, IconURL, and IconEmoji fields to AssistantThreadsSetStatusParameters, forwarded by SetAssistantThreadsStatusContext, matching the new optional parameters on assistant.threads.setStatus for customising the status-update presentation.
• Exposed SocketmodeHandler.DispatchEvent (previously the unexported dispatcher), enabling integration tests to exercise registered handlers without a live WebSocket connection. The unexported dispatcher is kept as

... (truncated)

Commits

• 34ad5c0 security: reject empty signing secret for NewSecretsVerifier
• c6edc27 chore: bump go to 1.25.9
• 35d8f31 chore: bump to v0.23.0
• ae59061 feat(block): add alert block (#1552)
• 2df5cfa feat(assistant): add username and icon to status update (#1553)
• e3c0e8b feat(block): add card and carousel blocks (#1551)
• 4c472cd feat(socketmode): expose socketmode handler dispatcher method (#1550)
• f482b19 chore: v0.22.0
• 3a5db9d chore: fix staticcheck errors (#1548)
• 19e0416 ci: add staticcheck
• Additional commits viewable in compare view