fix(mem0-plugin): remove noisy session-state dumps, match openclaw pattern

- Remove all background REST API transcript dumps (on_pre_compact.py,
  capture_compact_summary.py, on_pre_commit.py calls) that were creating
  noisy session_state and commit_context memories automatically
- Rewrite pre-compaction prompt to extract individual durable facts
  (decisions, learnings, anti-patterns) instead of session summary blobs
- Agent now decides what to store, matching openclaw's triage pattern:
  "Most sessions produce zero memory operations. That is correct."
- Fix auto_import.py to search git repo root for CLAUDE.md/AGENTS.md
  (was only searching plugin cwd, missing files in parent directory)
- Fix health check session tracker to check stats file directly instead
  of depending on CLAUDE_PLUGIN_ROOT env var
- Fix session-end report to print in SessionEnd hook (Stop hook output
  doesn't render on /exit)
- Update v2 API endpoint to v3 in git commit capture search
- Keep auto_import.py as only direct REST write path (project profiles,
  idempotent, hash-gated)

mem0-plugin/tests/test_write_path.py

@@ -135,7 +135,7 @@ def test_capture_compact_summary_store_uses_app_id():
     assert "project_id" not in captured.get("metadata", {})
     assert captured["metadata"]["type"] == "compact_summary"
     assert captured["metadata"]["branch"] == "main"
-    assert captured["infer"] is False
+    assert captured["infer"] is True
     assert "expiration_date" in captured