Pure classifier extracted from runPlanSkillObservation's polling loop so
unit tests can exercise the actual branch order with synthetic input
strings. Runner gains:
- env? passthrough on runPlanSkillObservation (forwarded to launchClaudePty).
gstack-config does not yet honor env overrides; plumbing is in place for a
future change to make tests hermetic.
- TAIL_SCAN_BYTES = 1500 exported constant. Replaces a duplicated magic
number in test/skill-e2e-plan-ceo-mode-routing.test.ts so tuning stays
in sync.
- isPermissionDialogVisible: the bare phrase "Do you want to proceed?" now
requires a file-edit context co-trigger. Other clauses unchanged. Skill
questions that contain the bare phrase are no longer mis-classified.
- classifyVisible(visible): pure function. Branch order silent_write →
plan_ready → asked → null. Permission dialogs filtered out of the
'asked' classification so a permission prompt cannot pose as a Step 0
skill question.
Adds 24 unit tests covering all classifier branches, edge cases, and the
co-trigger contract.
fa78a20188