#9 Expand spec to 102 operations, regenerate all 5 SDKs

Summary

• 32 new operations added to the Smithy spec (102 total, was 70): access tokens, account settings, board entropy/involvement, join codes, notification settings, push subscriptions, search, steps index, user role management
• 4 summary types removed (pre-1.0 breaking): UserSummary→User, BoardSummary→Board, ColumnSummary→Column, Pin→Card
• Go typed returns: generator resolves ResponseContent schemas to *generated.Type or []generated.Type
• Idempotent POST retry: WithIdempotent(ctx) in Go, retryable: true kwarg in Ruby — driven from behavior-model.json
• All 5 SDKs regenerated: Go, TypeScript, Ruby, Swift, Kotlin
• Conformance: 111 tests across 9 fixtures, 4 runners (Go, TS, Ruby, Kotlin), all passing
• RAILS-API-COMMUNIQUE.md: documents 28 JSON endpoints needed from Rails (implemented in https://github.com/basecamp/fizzy/pull/2675)

Breaking changes

Pre-1.0 SDK — no public consumers. These would be semver-major post-1.0:

Change	Impact
UserSummary deleted	Use User instead
BoardSummary deleted	Use Board instead
ColumnSummary deleted	Use Column instead
Pin / PinList deleted	ListPins returns Card / CardList
Tag.name → Tag.title	Field rename
NotificationCard.board → NotificationCard.board_name	Field rename
New required fields on Account, Tag, NotificationCard	Breaking for type constructors

Merge order

1. https://github.com/basecamp/fizzy/pull/2675 lands first (adds the 28 JSON endpoints the SDK expects)
2. This PR merges after Rails deploys
3. Integration test against staging to validate response shapes

Test plan

• make check passes (Smithy, OpenAPI, behavior model, url-routes, provenance, rubric audit, all 5 SDK checks, all 4 conformance runners)
• CI green on this branch
• Rails api-breadth deployed to staging
• SDK conformance run against live staging