Emit F# metadata and companion build and debug artifacts

Parent: #8
Blocked by: #38

Outcome

Produce the F#-specific semantic data and all compiler-owned companion artifacts required by downstream tools and consumers.

Acceptance criteria

• Implementation assemblies carry compatible F# signature and optimization metadata for cross-assembly F# consumption.
• Reference assemblies are true contract-only outputs rather than copies of implementation assemblies.
• Portable and embedded PDB data includes documents, checksums, SourceLink, sequence points, scopes, locals, imports, closures, and state-machine debug information where requested.
• XML documentation, embedded source, managed and native resources, deterministic identities, versioning, and all declared signing modes are emitted and validated.
• Four-way Oracle/FSharp2 producer-consumer tests localize metadata failures without making the test-only inspector semantic authority.
• Debugger evidence is admitted only after the pinned driver conformance gate.
• Transaction inputs remain symbolic until fresh final linking.

Decision inputs

Issues #7, #15, #17, and #18; ADRs 0002, 0006, 0021, 0023, and 0027.

This issue inherits the corpus-neutral acceptance policy in #8.

Start with the blocked prerequisite in issue #38, then read parent issue #8 and decision inputs #7, #15, #17, #18 plus ADRs 0002, 0006, 0021, 0023, and 0027. Done means satisfying the listed metadata, artifact, resource, signing, producer-consumer, debugger-conformance, and symbolic-linking acceptance criteria.