vedit: real author attribution (replace hardcoded "awidat agent")

[explicit09]

Problem

crates/core/src/vc/mod.rs:330 (awidat_author()) hardcodes Author { name: "awidat agent", email: "agent@awidat.local" }. Every commit path — commit_current_timeline, merge_refs, auto-commit — uses it, so every vedit commit is anonymous. This blocks user-authored notes, multi-seat editing, and meaningful vedit_blame attribution. It is the schema chokepoint for the entire right-hand side of the Collaboration category.

Scope (MVP)

• Add an override pathway: Option<Author> parameter, env-var fallback (AWIDAT_USER_NAME / AWIDAT_USER_EMAIL), or both.
• Keep awidat_author() (or a renamed default_awidat_author()) as the fallback so all existing tests/behavior stay green when no override is supplied.

Layers

1. crates/core/src/vc/mod.rs — refactor awidat_author() and its callers
2. commit_current_timeline, merge_refs, auto-commit chain — accept/pass-through the override
3. crates/core/tests/vedit_author.rs (new) — Author roundtrip via vedit_log

References

• Gap analysis: .reference-research/pro-editing-gap-analysis/11-collaboration.md (Status update 2026-05-21, [codex] harden atomic writes and checks #1 still-open item)
• In progress overnight on branch overnight slice: wave1-vedit-author — close when merged

[explicit09]

Closed by A3 merge: see awidat commit 75f39f5 (Merge A3: vedit author attribution). vc::awidat_author() renamed to default_awidat_author(); new CommitAuthor override pathway via explicit param + AWIDAT_USER_NAME/AWIDAT_USER_EMAIL env-vars; new commit_current_timeline_as / auto_commit_apply_as / merge_refs_as entry points; LogEntry.author field. Tests: crates/core/tests/vedit_author.rs (2 integration + 4 resolver unit). NOTE: desktop apply_edl handler still calls the legacy non-_as path — separate follow-up to wire it.