Emit workshop-rs/mapped-text-v1 from opy-provider

[e54-bot]

Readiness: ready-for-implementation once wrightkit/workshop-rs#272 lands (parallel with wrightkit/language-provider-protocol#39).

Decision: wrightkit/workshop-rs#271 · workshop-rs ADR-0013.

Goal

Emit workshop-rs/mapped-text-v1 from opy-provider so Workshop-level evidence can be attributed to authored .opy source.

Scope

• Return workshop-rs/mapped-text-v1 from lpp/compile only when the request accepts it; otherwise keep workshop-rs/text-v1.
• Build the mapping with the workshop-rs SourceMap from the spans lowering already attaches.
• Attribution policy (opy-rs owned): included files map to their own document URIs; macro-expanded code maps to the invocation site; generated helper nodes carry no span.

Non-goals

• Nested value mappings.
• Changes to OPY diagnostics or lowering output.

Acceptance criteria

• Mapped output only when accepted; unchanged text-v1 output otherwise (tested both ways).
• Column units match Position (1-based Unicode scalar values), tested with non-ASCII source.
• Multi-file projects: include-origin nodes carry their own URIs, matching provider document URIs.
• Macro-expanded nodes map to the invocation site; generated helpers are unmapped (tested).
• A pinned Bastion revision compiles to mapped-text-v1 whose mapping applies to the re-parsed Workshop text without shape mismatch.