feat(feeds): add reaction write outcome fields

[JimmyPettersson85]

Summary

Adds three new fields to AddReactionResponse and AddCommentReactionResponse, from the v2 serverside spec:

Field	Type	Meaning
outcome	string — created | replaced | unchanged	what the write did to the user's reaction on the target
previous_reaction_type	string?	the reaction type enforce_unique removed
counter_delta	number — 0 | 1	change to the user's reaction count on the target

Backend PR: GetStream/chat#17241 (FEEDS-1886). With enforce_unique=true the previous reaction is replaced silently, and nothing in the response told the caller whether the reaction was new or a swap — so a customer keeping their own per-user reaction counter had to read before writing, or delete-then-add.

Counting recipe: add → outcome === 'created' ? +1 : 0; delete → 2xx ? -1 : 0.

Scope

This is deliberately not a full regeneration. src/gen was last refreshed on 2026-09-07, so a wholesale regen also pulls in every unrelated spec change since then — skip_own_followings, activity_marks, unity device fields, the user-interests endpoints, and additional optional params across the chat, common, moderation and video APIs. That was the first version of this PR and it failed channel-types.test.ts.

This version resets src/gen to main and adds only the two reaction response interfaces: 30 insertions, 0 deletions, 1 file. Catching the rest up to the spec is worth doing, but as its own PR where a failure is attributable.

Merge order

Merges before the backend, per the usual flow: SDKs merge and release first, then the chat repo bumps its pinned SDK versions, then GetStream/chat#17241 merges.

Generated from that PR's branch spec, so if its API surface changes during review this needs updating before release.

Testing

• prettier --check clean, tsc --noEmit clean.
• Field definitions taken verbatim from the generator output, so they match what a future full regen will produce.

🤖 Generated with Claude Code