fix(evals): strip evals sigil before root fallback to run handler

[chromiebot]

When user input like evals act hits the unknown-token root fallback, the full tokens array (including the leading "evals") was forwarded to the run handler. parseRunArgs would then misinterpret "evals" as a target or flag.

Strip the leading "evals" token before delegating to the run handler so only the intended arguments are forwarded.

Addresses cubic-dev-ai review comment on PR #2100.

why

what changed

test plan

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Summary by cubic

Fixes a parsing bug where inputs like evals act were sent to the run handler with the evals sigil included, causing parseRunArgs to misinterpret it. We now strip the leading evals token before delegating so only the intended args are passed.

• Bug Fixes
  • Strip leading evals token in the root fallback before invoking the run handler.
  • Added a test to ensure ["evals", "act"] dispatch forwards ["act"].

^{Written for commit 9a6fab5. Summary will update on new commits.}

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