fix(core): allow mode=static with no repos and no path

[christso]

Summary

• When workspace.mode=static is set without workspace.path and there are no repos, fall back to temp mode instead of erroring
• The static mode's purpose is to skip repo cloning, which is already a no-op when there are no repos — so the path requirement is unnecessary in this case

Changes

• packages/core/src/evaluation/orchestrator.ts: Move the useStaticWorkspace derivation after the new fallback check. When mode=static + no path + no repos, downgrade configuredMode to temp so a temp directory is created automatically
• packages/core/test/evaluation/orchestrator.test.ts: Updated existing test to verify the error still fires when repos are present; added new test verifying the fallback succeeds with no repos

Test plan

• Existing test updated: mode=static without path with repos still errors
• New test: mode=static without path and without repos falls back to temp mode and succeeds
• All 1618 core tests pass
• Pre-push hooks pass (build, typecheck, lint, test, validate examples)

Closes #1082

🤖 Generated with Claude Code

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View logs

[christso]

Red/Green UAT

Eval file (mode: static, no path, no repos):

workspace:
  mode: static
tests:
  - id: test1
    input: "Say hello"
    assert:
      - type: contains
        value: hello

RED (main) — setup error

{"execution_status":"execution_error","error":"workspace.mode=static requires workspace.path or --workspace-path","failure_stage":"setup"}

GREEN (fix branch) — eval runs successfully

{"execution_status":"quality_failure","scores":[{"name":"contains-hello","type":"contains","score":0,"verdict":"fail"}]}

The quality_failure is expected — --dry-run returns mock output that doesn't contain "hello". The important thing is there's no setup error and the eval actually executes.