pub const ENVELOPE_FORMAT_VER: u32 = 3; // 3u32Expand description
Wire-format version of the ObsEnvelope / ObsBatch shape.
Bumped to 2 alongside the move from JSON-payload (Phase-1
#[derive(Event)]) to buffa-encoded payload bytes for both
authoring paths (decision D6-1 in spec 93).
Bumped to 3 in Phase 7 alongside spec 94 § P0-A:
ObsSpanCompleted / ObsSpanEntered gained typed
trace_id/span_id/parent_span_id fields and the bridge
switched from raw-byte payloads to buffa-encoded typed payloads
(spec 94 § P1-B). Both producers and consumers therefore must
agree on the new wire shape. Any further change to the field
layout of obs/v1/envelope.proto (adding, removing, renumbering,
or repurposing fields) requires bumping this constant and the
corresponding format_ver field on every encoder/decoder. The CI
guard at .github/workflows/format-ver-guard.yml fails any commit
that touches envelope.proto without also bumping this value.
Spec 90 § 3.3 / spec 93 § 1 P0-2 + decision D6-1 / spec 94 D7-1.