refactor(cli): remove dead outcome helpers and unify MakaRunOutcome classification

Problem

Three dead / duplicated outcome paths in packages/cli:

1. sandbox-boundary-failure.ts — invocationHasSandboxBoundaryFailure / invocationRecoveredSandboxBoundaryFailure have zero callers (they are the last consumers of the removed runtime's InvocationResult). The live sibling sessionEventSandboxBoundaryFailureReason must stay.
2. MakaRunOutcome is computed twice from two sources in runtime-host-run-command.ts — a live TurnOutcomeAccumulator (SessionEvent stream) and a stored-message classifier (outcomeFromStoredTurn / storedSandboxBoundaryOutcome) whose vocabularies already diverge (aborted/runtime_error vs errorClass ?? abortSource ?? status).
3. Dead exports with no callers: formatResumeHint, cleanRecapText/RECAP_INSTRUCTION, runMakaTextCli, colorDiffRow.

Desired outcome

One MakaRunOutcome classifier parameterized over its source, dead helpers removed, dead exports dropped.

Alternatives or workarounds

Leave the divergence; the stored-message path already produces different failure classes from the live path.

Acceptance

• invocationHasSandboxBoundaryFailure / invocationRecoveredSandboxBoundaryFailure removed; sessionEventSandboxBoundaryFailureReason retained
• One outcome classifier shared by the live and stored-message paths
• Dead exports removed
• maka run and maka run --graph exit codes pinned by CLI tests; typecheck and Biome pass

Related

• #3034, #3035 (prior runtime path removals)