Brummel
8c9a1b4630
A real OHLC source now builds from aura-ingest alone, in the engine-native epoch-ns Timestamp currency, with the one ms<->ns crossing owned by the seam. Library surface (src/lib.rs), all additive — the ms-based `open` and `unix_ms_to_epoch_ns` are untouched, so every existing call site is preserved byte-for-byte: - epoch_ns_to_unix_ms (private): the seam-owned inverse; consumers never convert (#80). - M1FieldSource::open_window: the Timestamp-window mirror of `open`, mapping each bound through the private inverse and delegating to `open`. - open_ohlc: the canonical OHLC bundle opener — four M1FieldSources in the fixed open/high/low/close C4 merge order, sharing one Arc<DataServer> (one cache, C12); the order lives in one vetted place (#92). - default_data_server + `pub use data_server::{DataServer, DEFAULT_DATA_PATH}`: a real-data source builds without naming the external data_server crate (#81). Consumer migration: the shared breakout_real.rs helpers and every GER40 example/test move to the Timestamp-native surface — open_ohlc_sources removed, utc_month_window_ms -> utc_month_window (Timestamp), report_from_trace retyped, the per-consumer ns_to_ms hand-divides deleted, the direct data_server imports replaced by the re-exports. ger40_breakout_compare.rs (which opened OHLC by its own hand-loop, reached by neither retyped helper) is migrated by inspection. Return type is Vec, not [_; 4]: Harness::run consumes Vec<Box<dyn Source>>, so it feeds straight in; order-safety comes from the single helper either way. Tests: a hermetic round-trip pinning the inverse; a gated behaviour-preservation test (open_ohlc Timestamp path == ms-path open, bit-identical recorded series); a hermetic absent-archive fixture pinning the file-level None contract and the #81 re-export firewall. Verified: cargo build --workspace --all-targets clean; cargo test --workspace green (the gated GER40 tests ran against the local archive — open_ohlc_seam proves byte-identity on real data, not a skip); clippy --all-targets -D warnings clean. Acceptance greps pass: open_ohlc_sources gone, no consumer-side ns_to_ms, no data_server import in any migrated GER40 consumer, epoch_ns_to_unix_ms private. closes #80, #81, #92