add auditable Swiss gulika calculator

docs/research/pre_work_error_ledger.md

@@ -89,6 +89,7 @@ For large architecture or release work, also read:
 | ERR-056 | A WorkBuddy checkout of the same remote diverged substantially from the active source branch and can be mistaken for a mergeable mirror. | active | Read `whole_machine_fragment_sweep_2026_07_14.md`; do not copy or merge it without explicit commit-level review on a separate branch. |
 | ERR-057 | The release quality profile checked untracked files but did not execute the privacy AST scan or the real Chromium report-isolation probe. | mitigated 2026-07-14 | `release_hygiene_check()` now requires `public_release_privacy_scan.py --json` and `report_renderer_isolation_poc.py --strict`; parity manifest validation also runs as a contract check. |
 | ERR-058 | Formula-based Sahams used the day/night operand rules but omitted the documented zodiacal-order `+30°` exception. | mitigated 2026-07-14 | `_calc_formula_saham()` applies the `references/saham_rules.json` forward-arc condition and one-sign correction; keep external numeric oracle parity as a separate `partial` requirement. |
+| ERR-059 | Gulika was either an approximate fallback or falsely implied as a chart module output. | mitigated 2026-07-14 | `scripts/gulika.py` computes Prasna Marga Ghatika segment Ascendant with Swiss sunrise/sunset and Lahiri sidereal houses; registry is `partial` and exposes only the actual calculator until external numeric parity and chart integration are complete. |
 
 ## Fragment Sweep Command Set
 

references/technique_registry.json

@@ -420,7 +420,7 @@
         "upagraha",
         "event"
       ],
-      "status": "blocked",
+      "status": "partial",
       "knowledge_refs": [
         "references/prashna-complete-guide.md"
       ],
@@ -430,17 +430,16 @@
         "full-reading"
       ],
       "output_paths": [
-        "modules.chart.upagraha",
-        "scripts/prashna.py:calc_gulika_simple"
+        "scripts/gulika.py:calculate_gulika"
       ],
       "audit_label": "Upagraha/Gulika/Maandi",
-      "missing_impact": "Sensitive malefic shadow points are unavailable, weakening pressure, delay and vulnerability interpretation.",
+      "missing_impact": "Swiss day/night and Prasna Marga Ghatika Gulika are available as supporting evidence; Maandi, other Upagrahas and external numeric parity remain unavailable.",
       "entry_type": "supporting_indicator",
       "evidence_role": "secondary",
       "user_visibility": "expert_audit",
       "verification_level": {
-        "calculation": "verified",
-        "rule": "verified",
+        "calculation": "partial",
+        "rule": "partial",
         "prediction": "support_only"
       },
       "conclusion_policy": "Supporting evidence only; it can raise/lower confidence but cannot by itself decide an event or timing claim."

scripts/gulika.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+"""Swiss-Ephemeris Gulika calculator using the Prasna Marga Ghatika table."""
+from __future__ import annotations
+
+from datetime import datetime
+from typing import Any
+
+import swisseph as swe
+
+try:
+    from saham_daynight import determine_daytime
+except ImportError:
+    from scripts.saham_daynight import determine_daytime
+
+
+# Monday=0, matching datetime.weekday(). Values are the end of Saturn's share
+# measured in Ghatika from the relevant sunrise/sunset (30 Ghatika per period).
+GHATIKA_END = {
+    0: {"day": 22, "night": 6},
+    1: {"day": 18, "night": 2},
+    2: {"day": 14, "night": 26},
+    3: {"day": 10, "night": 22},
+    4: {"day": 6, "night": 18},
+    5: {"day": 2, "night": 14},
+    6: {"day": 26, "night": 10},
+}
+
+
+def _sidereal_ascendant(jd_ut: float, lat: float, lon: float) -> float:
+    swe.set_sid_mode(swe.SIDM_LAHIRI)
+    cusps, ascmc = swe.houses_ex(jd_ut, lat, lon, b"P", swe.FLG_SIDEREAL)
+    return float(ascmc[0]) % 360
+
+
+def calculate_gulika(
+    moment: datetime,
+    *,
+    lat: float,
+    lon: float,
+    tz: float,
+) -> dict[str, Any]:
+    """Return Gulika from local moment/location using Swiss sunrise and sunset."""
+    daynight = determine_daytime(moment, lat=lat, lon=lon, tz=tz)
+    is_day = bool(daynight["is_daytime"])
+    period = "day" if is_day else "night"
+    ghatika_end = GHATIKA_END[moment.weekday()][period]
+    start_jd = daynight["sunrise_jd_ut"] if is_day else daynight["sunset_jd_ut"]
+    end_jd = daynight["sunset_jd_ut"] if is_day else daynight["sunrise_jd_ut"] + 1.0
+    if end_jd <= start_jd:
+        end_jd += 1.0
+    segment_jd = start_jd + (end_jd - start_jd) * (ghatika_end / 30.0)
+    longitude = _sidereal_ascendant(segment_jd, float(lat), float(lon))
+    return {
+        "scope": "gulika_prasna_marga",
+        "status": "partial",
+        "longitude": round(longitude, 6),
+        "sign_idx": int(longitude / 30) % 12,
+        "degree_in_sign": round(longitude % 30, 6),
+        "period": period,
+        "weekday": moment.weekday(),
+        "ghatika_end": ghatika_end,
+        "segment_jd_ut": segment_jd,
+        "daynight_evidence": daynight,
+        "ayanamsa": "lahiri",
+        "rule_source": "references/prashna-complete-guide.md#3.5",
+        "boundary": "Formula is implemented from the local classical guide; external JHora/PyJHora numeric parity remains required before enabling Sphuta or verdict layers.",
+    }

tests/test_gulika.py

@@ -0,0 +1,17 @@
+from datetime import datetime
+
+from scripts.gulika import GHATIKA_END, calculate_gulika
+
+
+def test_gulika_uses_prasna_marga_weekday_table() -> None:
+    assert GHATIKA_END[6] == {"day": 26, "night": 10}
+    assert GHATIKA_END[0] == {"day": 22, "night": 6}
+
+
+def test_gulika_returns_sidereal_segment_ascendant_with_audit_trace() -> None:
+    result = calculate_gulika(datetime(1990, 6, 15, 12, 0), lat=39.9042, lon=116.4074, tz=8)
+
+    assert result["status"] == "partial"
+    assert 0 <= result["longitude"] < 360
+    assert result["ghatika_end"] in range(0, 31)
+    assert result["rule_source"].endswith("#3.5")