feat: split ccb_build into ccb_feature (20 tasks) + ccb_refactor (20 tasks)

Restructure the mixed ccb_build suite into two focused suites for
finer-grained capability analysis:

- ccb_feature: 10 migrated + 10 new feature/implementation tasks
- ccb_refactor: 7 migrated + 13 new cross-file refactoring tasks
- Scrapped 8 DI-Bench deps-install + 3 broken build-config tasks
- ABC audits passed: false-pass checks (features), symbol existence (refactors)
- 2 feature replacements after audit (istio-retry-budget, linux-procfs)
- 3 refactor symbol fixes after audit (numpy, curl, prometheus)

Updated: selected_benchmark_tasks.json, docs (TASK_SELECTION, LEADERBOARD,
TASK_CATALOG, REPORT_CONTEXT, WORKFLOW_METRICS, CONFIGS, QA_PROCESS),
run_dir_prefix_map.json, feature_2config.sh, refactor_2config.sh.

Total: 199 SDLC + 95 MCP-unique = 294 tasks across 9+11 suites.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: sjarmak