bridge: naming-clarity refactor for broker/webhook payloads

[benvinegar]

Summary

Naming-clarity-only refactor to make request/response/payload variable names explicit by domain/context across Slack bridge and broker registration code.

Before -> After highlights

• payload -> registerRequestBody, brokerResponseBody, slackEventEnvelopePayload
• body -> brokerRequestBody, rawApiRequestBody, apiRequestBody, brokerPubkeyResponseBody, registerResponseBody
• response -> brokerHttpResponse, brokerPubkeyResponse, registerResponse
• params -> sendRequestBody / reactRequestBody / slackApiRequestBody
• sendViaBroker input body -> actionRequestBody
• signProtocolRequest input payload -> protocolRequestPayload

Scope

• bin/broker-register.mjs
• slack-bridge/broker-bridge.mjs
• slack-bridge/bridge.mjs
• slack-bridge/security.mjs

Validation

• npm run typecheck
• npm test
• npm run lint:js

Behavior

No business logic, endpoint behavior, DB/schema behavior, or API contract changes. This PR is naming/refactor-only.

[greptile-apps]

Greptile Summary

This PR performs a systematic naming-clarity refactor across broker registration and Slack bridge code. Variable names are made explicit by domain/context to improve code readability and maintainability.

Key changes:

• Renamed generic response/body/payload/params variables to domain-specific names
• bin/broker-register.mjs: payload → registerRequestBody, response → brokerPubkeyResponse/registerResponse, body → brokerPubkeyResponseBody/registerResponseBody
• slack-bridge/broker-bridge.mjs: payload → brokerResponseBody/slackEventEnvelopePayload/protocolRequestPayload, body → brokerRequestBody/actionRequestBody, response → brokerHttpResponse, introduced responseHeaders local variable
• slack-bridge/bridge.mjs: body → rawApiRequestBody, params → apiRequestBody
• slack-bridge/security.mjs: params → sendRequestBody/reactRequestBody

All changes are mechanical renames with no functional, logic, or API contract modifications. The refactor improves code clarity by making request/response variable names explicit about their origin and purpose.

Confidence Score: 5/5

• This PR is safe to merge with no risk
• Pure naming refactor with zero functional changes. All modifications are mechanical variable renames that improve code clarity. No logic, API contracts, or behavior modified. Tests pass per PR description.
• No files require special attention

Important Files Changed

Filename	Overview
bin/broker-register.mjs	Renamed variables for clarity: response → brokerPubkeyResponse/registerResponse, body → brokerPubkeyResponseBody/registerResponseBody, payload → registerRequestBody. All changes are mechanical renames with no logic changes.
slack-bridge/bridge.mjs	Renamed variables for clarity: body → rawApiRequestBody, params → apiRequestBody. Consistent renaming across all API endpoints (/send, /reply, /react). No behavior changes.
slack-bridge/broker-bridge.mjs	Comprehensive naming refactor: payload → brokerResponseBody/slackEventEnvelopePayload/protocolRequestPayload, body → brokerRequestBody/actionRequestBody/apiRequestBody, response → brokerHttpResponse, params → slackApiRequestBody. Added responseHeaders local variable. All changes are mechanical renames.
slack-bridge/security.mjs	Renamed function parameters: params → sendRequestBody/reactRequestBody in validation functions. Consistent with the naming convention across the codebase.

_{Last reviewed commit: cf5f17f}