Fix chat routing drift and remove one-line copy shortcut

[adgk2349]

Summary

• Route generic "제안해줘" requests back to GENERAL_CHAT unless they are file/search/summary actions.
• Add early direct count/list intercept in general chat execution to avoid downstream path leakage.
• Remove direct one-line shortcut path so "방금 내용 한 줄" is handled by model summarization, not text copy.
• Keep/expand deterministic direct responses for count-based conversational requests.

Root Cause

• 제안해줘 was broadly mapped to LIGHTWEIGHT_ACTION_REQUEST, causing some conversational turns to go through local_rag unexpectedly.
• One-line follow-up had a direct return path (direct_one_line_summary) that reused previous text instead of model summarization.

Validation

• Reproduced and verified with manual turn simulation report:
  • sidecar/stream_turn_report_20260522_alttopic_v7.json
• Key check passed:
  • "이번엔 운동 루틴 2개만 제안해줘" now returns runtime_detail=direct_count_early;count=2.

Scope

• sidecar/local_ai_core/nlu/intent_parser.py
• sidecar/local_ai_core/reasoning/strategies/general_chat_sections/general_chat_execution_mixin.py
• plus related parser/memory/conversation utility updates included in this branch commit history.