feat(nodes-from-anchor): add event support to V00 anchor IDLs

[stegaBOB]

Old (V00) anchor IDLs define events inline with fields and rely on a SHA256("event:EventName") discriminator. Bring V00 in line with V01 by emitting EventNodes for these IDLs.

[changeset-bot]

🦋 Changeset detected

Latest commit: f77f67e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@codama/nodes-from-anchor	Minor

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[stegaBOB]

Could probably make an argument for this to be a patch bump? Minor seems like a lot. I don't have a preference one way or the other

[lorisleiva]

@trevor-cortex

[trevor-cortex]

Brings V00 anchor IDLs in line with V01 by emitting EventNodes, using the classic sha256("event:<PascalCase>")[0..8] discriminator scheme. The shape of the produced node (hidden-prefix struct + constant discriminator) matches eventNodeFromAnchorV01 exactly, which is what we want.

Things that look right:

• Origin gating in ProgramNode.ts (origin === 'anchor' ? … : []) mirrors how accountNodeFromAnchorV00 only attaches anchor discriminators when origin === 'anchor'. Correct — shank IDLs reusing the V00 schema shouldn't get anchor event semantics.
• 8-byte fixed-size constant matches Anchor's classic prefix.
• IdlV00EventField is structurally compatible with what structTypeNodeFromAnchorV00 reads (name + type); the index flag is effectively ignored, which matches actual on-chain behavior for V00 anchor events (no real indexing in the emitted bytes).
• Changeset is a minor bump on a pre-1.0 package — appropriate for a user-facing additive feature.

Notes for subsequent reviewers:

• Worth a quick sanity check that the expected discriminator 60b8c5f38b025a94 for MyEvent matches what anchor itself emits — easy to verify against any real V00 anchor IDL with events (e.g. an older Metaplex program).
• No "event type missing" error path like V01 has, but that's by design: V00 defines event fields inline, so there's no separate type def to look up.

LGTM.