Extend canonical WIR rule events for DEL/OSTW provider integration

[Teakowa]

Goal

Extend the canonical Workshop rule-event model so downstream source-language providers can represent and emit the full evidence-backed Workshop event surface without inventing provider-local event encodings.

Context

Wright v0.2.4 consumes workshop-rs revision 7b0f8c38b9d1ee627565e8406de25293df9b4f7f as the canonical Workshop core. At that revision, workshop_rs::wir::Event represents only Global, EachPlayer, and Subroutine.

del-rs now begins its Workshop integration phase (#8). Its pinned DEL/OSTW compatibility inventory requires 11 rule event forms plus subroutines: ongoing global/player, elimination/final-blow, damage dealt/taken, death, healing dealt/taken, player join, and player leave. This exposes a canonical-WIR gap rather than a DEL frontend gap.

The DEL inventory is evidence that downstream providers need these capabilities; canonical Workshop identities, spellings, parameter shapes, and locale mappings remain owned and evidenced here.

Scope

• Define a locale-independent WIR representation for the declared Workshop rule-event forms and their event parameters/filters where applicable.
• Extend the canonical catalog/event metadata only where required by independently reviewed Workshop evidence.
• Parse supported raw Workshop event blocks into the canonical representation.
• Emit the canonical representation through the existing locale-aware emitter for supported locales.
• Validate event identities/arguments through the canonical catalog/semantic layer.
• Preserve source provenance through event parsing and emission diagnostics where the WIR contract supports it.
• Keep existing ongoing-global, ongoing-player, and subroutine behavior compatible or provide an explicit migration path for current consumers.
• Add focused parse/validate/emit/round-trip tests for each newly declared event form and relevant parameter combinations.

Non-goals

• Adding DEL/OSTW-specific AST/HIR types or source-language semantics to workshop-rs.
• Encoding provider-specific rule syntax such as Event.OnDamageDealt in the canonical model.
• Guessing event spellings or parameter semantics from downstream source-language names.
• Requiring byte-identical text output when canonical Workshop semantics are equivalent.
• Expanding unrelated Workshop actions/values/settings in the same change.

Acceptance criteria

• The canonical WIR can represent every reviewed rule-event form needed by the declared DEL/OSTW surface without provider-local event enums or stringly-typed fallbacks.
• Raw Workshop parser and emitter round-trip each supported event form through locale-independent WIR.
• Event identities and parameters are catalog/validation-backed and carry explicit evidence/provenance.
• Existing Wright/workshop-rs consumers remain regression-green.
• del-rs can consume the public event contract without copying canonical Workshop event data.

Relationships

• Builds on Establish the canonical multi-locale Workshop core #2 canonical core.
• Supports wrightkit/del-rs#8 Workshop integration.
• Conformance evidence should align with Establish an evidence-driven Workshop conformance corpus and seasonal feature census #10 where its feature identities/corpus are available.