feat(narayana): label the product Narayana as the legacy algorithm (T4, BUG-1215)

Round-4 ruling Q4 / product decision A: scoring and the consultation and
report time axes keep the old Narayana (from the Lagna, always zodiacal) until
the Rath trial is decided; every user-visible Narayana now says so.
narayana_legacy_label adds profile=legacy_reference_only and the note (zh/en)
at the consumers (consultation modules, full reading Step 4.13, CLI), not in
the frozen narayana_dasha.py (ERR-110/115). The card's timing.narayana carries
'algorithm'; the projection allowlist passes algorithm_note; the reference
report's Narayana section and the dasha-family table show '算法：…' (English
twin in the phrase table). The unused narayana-dasha --variant-profile flag,
the one place offering a Chara Dasha author's profile for Narayana, is removed.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N4f2nya58RoRu4yEmJgRGE

scripts/pl9_reader_export.py

@@ -23,6 +23,10 @@ for the public reader rather than exposing empty or machine-key rows.
 
 from __future__ import annotations
 
+try:  # scripts/ on sys.path
+    from narayana_legacy_label import LEGACY_NOTE_ZH
+except ImportError:  # pragma: no cover - package import
+    from scripts.narayana_legacy_label import LEGACY_NOTE_ZH
 import re
 
 SIGNS: list[str] = []
@@ -1652,9 +1656,11 @@ def render_pl9_parity_markdown(packet: dict) -> str:
             periods = _list(family.get('periods'))
             if not periods:
                 continue
+            lines.extend([f'### p{page} {title_text}', ''])
+            if 'Narayana' in title_text:
+                # BUG-1215: the product Narayana is the legacy algorithm.
+                lines.extend([f'- 算法：{LEGACY_NOTE_ZH}', ''])
             lines.extend([
-                f'### p{page} {title_text}',
-                '',
                 '| 序号 | 主星/星座 | 起始 | 结束 | 年数 |',
                 '|------|-----------|------|------|------|',
                 ])