implementation-executionlisted

# Implementation Execution Once direction is clear, implement end-to-end in one cohesive pass. Approval is for the chosen direction, not for incomplete core-logic fragments. A complete change includes all required integration points, imports, types, schemas, configuration, critical edge cases/error handling, backward compatibility unless a break was approved, and relevant tests when an existing framework exists. Leave no debug output, dead code, placeholders, pseudo-code, or unnecessary dependencies. Follow repository conventions and avoid unrelated changes. Before the first execution/build step, when several required runtime, dependency, compiler, or tool prerequisites are already knowable, check them in one grouped probe instead of discovering them one failure at a time. Resolve only confirmed missing prerequisites and respect existing dependency/approval policy; do not install speculative packages or turn a small task into environment setup. A later probe is justified only by new evidence from the first execution. Treat polling as a costed execution step. If a command is still running and the harness returns control, wait in coarse intervals appropriate to the expected duration — normally at least 30 seconds for builds or test suites — instead of repeatedly checking with short polls. Do not send empty/no-op input only to peek, and do not poll at all when the execution call already blocks until completion. Poll sooner only when the command is expected to finish quickly