[0xFantomMenace]

The 0xArchive API now serves 1-minute buckets (interval=1m) on funding, open interest, price, liquidation-volume and breadth history, on every venue. Order flow now honors its bucket parameter, with 1m (default), 5m, 15m and 1h, and reads a sent cursor.

In this crate, funding, open interest and HIP-3 breadth history type interval as OiFundingInterval, which had no 1-minute variant. Liquidation volume, prices and order flow take a String and already pass "1m" through. OrderFlowParams and Hip4OrderFlowParams had no cursor.

The API does not return next_cursor on order flow yet. That arrives with an API switch, after SDK releases that forward the cursor are published. So this PR adds cursor but does not document paging by next_cursor; the paging docs are in draft #14, held until the switch is on.

Changes

• OiFundingInterval::OneMinute ("1m").
• Breadth history rustdoc lists 1m.
• OrderFlowParams::interval and Hip4OrderFlowParams::interval document the buckets the API serves.
• cursor: Option<String> on OrderFlowParams and Hip4OrderFlowParams, sent by orders.flow() (core and HIP-3) and hip4.get_order_flow(): a resume point in Unix milliseconds, and the response starts at the first bucket that opens after it. The field and method docs say start is inclusive, end exclusive, limit is the maximum number of buckets (default 1000, max 10000), a response holds the oldest limit buckets, and buckets are labelled by open time in UTC. The README order-flow example is a single request.
• Tests: every OiFundingInterval variant maps to its wire value; OneMinute is sent as interval=1m by funding, open interest and HIP-3 breadth history (wiremock, one expected hit per route).
• Test (wiremock): the order-flow cursor is sent on core, HIP-3 and HIP-4, the first request carries none, and a next_cursor in the response is surfaced. It fails when the cursor is not sent.
• CHANGELOG: an Unreleased entry, including that order-flow next_cursor arrives with an API switch.

Semver note

OiFundingInterval is not #[non_exhaustive], so downstream code that matches it without a wildcard arm will need a OneMinute arm. The order-flow param structs gain a public field, so a struct literal that lists every field needs cursor: None (or ..Default::default()). The changelog says both; pick the version bump accordingly at release.

Test plan

• cargo test --all-targets: pass (coverage_contract 16 of 16, including the 3 new tests). cargo test --doc: 8 passed.
• cargo fmt --check reports no diffs in the lines this PR changes. The crate has existing rustfmt drift elsewhere, left alone here.
• Checked against the live API: interval=1m and 15m on order flow return 1-minute and 15-minute buckets, a sent cursor starts the response after it, and the response carries no next_cursor.