Redirects dropped on handler dispatch

When a command resolved to a handler — a runtime alias or a within [handlers:] / [handler:] entry — its fd redirect targets were evaluated but never installed, so git log > out.txt under a git alias silently wrote nothing to the file. The handler dispatch arm did not wrap its body in with_redirects the way the Env, Builtin, and External arms did — an oversight from when handlers were added, not a deliberate semantics.

The fix (270ca13, 2026-05-27) wraps the handler arm in the same redirect frame as the others, so a redirect on a handled command takes effect and any command the handler forwards to inherits the frame:

• Where — core/src/evaluator/command_call.rs, the Resolution::Handler arm.
• Covered — ral/tests/pipeline.rs asserts all fd directions (stdout, stderr, stdin), both handler forms (per-name and catch-all), the value-returning mock case, and a pipeline-stage handler.

See also effects-handlers, evaluator.