[kartojal]

Adds DIRECTIONAL_SPLIT, DIRECTIONAL_MERGE, THRESHOLD_COMPOSE and THRESHOLD_DECOMPOSE activity types. Threshold rows report the moved line position as shares, since no collateral moves and the feed serves 0 in usdc_size. Titles, slugs and outcome labels are optional on all four types.

Rows with any other type no longer fail the page. They carry only the shared account fields, and their type is an OpaqueActivityType built on a private unique symbol. It never overlaps a listed ActivityType, so comparing activity.type with an ActivityType member still narrows each row, while exhaustive switches need a default branch. At runtime type stays the served string.

Python parity: Polymarket/py-sdk#404.

🤖 Generated with Claude Code

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Note

Medium Risk
Breaking public types on a core feed model may require consumer migrations; runtime parsing behavior changes for unknown activity types (graceful degradation vs. previous failure).

Overview
Adds four range-event activity variants to ActivityType and the Activity union: event-scoped DIRECTIONAL_SPLIT / DIRECTIONAL_MERGE (USD amount, optional event metadata, no single-market conditionId) and line-scoped THRESHOLD_COMPOSE / THRESHOLD_DECOMPOSE (required conditionId, shares from wire size instead of collateral). They are valid listActivity type filter values via the updated enum.

Forward compatibility: wire type is parsed as any non-empty string instead of a strict enum, so rows whose type is not yet listed normalize to shared account fields only with an OpaqueActivityType—activity pages no longer fail when the API ships new types first.

Breaking TypeScript behavior: activity.type is no longer a string or usable as a record key; consumers need String(activity.type) for labels/maps and a default branch (plus new cases) in exhaustive switches. Docs and a changeset describe the migration.

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