Replace ApplyCommonActions with ActionHandler interface

[peyton-alt]

No description provided.

[Copilot]

Pull request overview

Refactors the session state-machine transition flow to replace the “apply common actions + return remaining actions” pattern with a session.ActionHandler interface, so strategy-specific side effects can be dispatched during transition application.

Changes:

• Introduces session.ActionHandler + session.ApplyTransition(...) and updates tests accordingly.
• Updates strategy.TransitionAndLog(...) to accept an ActionHandler and applies transitions + actions in one place.
• Refactors manual-commit PostCommit/TurnEnd flows to use per-transition handlers and updates hook call sites to provide handlers (or NoOpActionHandler).

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
cmd/entire/cli/strategy/strategy.go	Updates the TurnEndHandler contract to provide a turn-end ActionHandler.
cmd/entire/cli/strategy/session_state.go	Updates TransitionAndLog to accept an ActionHandler and call session.ApplyTransition.
cmd/entire/cli/strategy/session_state_test.go	Adds coverage ensuring TransitionAndLog still applies phase changes even if the handler errors.
cmd/entire/cli/strategy/phase_postcommit_test.go	Adjusts post-commit/turn-end tests to validate emitted actions via result.Actions and apply via ApplyTransition.
cmd/entire/cli/strategy/manual_commit_hooks.go	Refactors PostCommit and turn-end dispatch into ActionHandler implementations.
cmd/entire/cli/session/phase.go	Adds ActionHandler, NoOpActionHandler, and ApplyTransition to execute common + strategy actions.
cmd/entire/cli/session/phase_test.go	Replaces ApplyCommonActions tests with ApplyTransition and handler-behavior tests.
cmd/entire/cli/hooks_claudecode_handlers.go	Updates turn-end/session-stop transitions to pass an ActionHandler (strategy-provided or no-op).
cmd/entire/cli/hooks.go	Updates session-start transition to pass session.NoOpActionHandler{}.