fix: correct axis 4 and 5 pole labels and flip orientation in SVD_THEMES

Axes 4 and 5 had inverted sign conventions relative to actual party votes.
Diagnostic confirmed SP/PvdD scored negative on axis 4 (free trade motions)
and FVD scored negative on axis 5 (secular motions), opposite to their
voting behaviour. Fix: swap positive_pole/negative_pole for both axes and
set correct flip direction so progressive parties appear on the left.

explorer.py

@@ -251,21 +251,27 @@ def load_party_axis_scores(db_path: str) -> Dict[str, List[float]]:
 
 
 def _render_party_axis_chart(
-    party_scores: Dict[str, List[float]], comp_sel: int
+    party_scores: Dict[str, List[float]], comp_sel: int, theme: dict
 ) -> None:
     """Render a 1D horizontal Plotly scatter of party positions on SVD axis `comp_sel`.
 
     Each party is plotted at its score on a single horizontal axis (y=0).
+    When theme['flip'] is True the scores are negated so that the progressive/left
+    side always appears on the left of the chart.
     """
     if not party_scores:
         st.caption("_Partijdata niet beschikbaar voor deze as._")
         return
 
     axis_idx = comp_sel - 1  # 0-based index into the 50-dim vector
+    flip = theme.get("flip", False)
     data: list[dict] = []
     for party, vec in party_scores.items():
         if axis_idx < len(vec):
-            data.append({"party": party, "score": vec[axis_idx]})
+            score = vec[axis_idx]
+            if flip:
+                score = -score
+            data.append({"party": party, "score": score})
 
     if not data:
         st.caption("_Geen partijscores voor deze as._")
@@ -276,9 +282,17 @@ def _render_party_axis_chart(
     colours = [PARTY_COLOURS.get(p, "#9E9E9E") for p in parties]
     hover = [f"{p}: {s:.3f}" for p, s in zip(parties, scores)]
 
+    # Determine axis labels: left = progressive pole, right = conservative pole
+    pos_pole = theme.get("positive_pole", "")
+    neg_pole = theme.get("negative_pole", "")
+    left_label = pos_pole if flip else neg_pole
+    right_label = neg_pole if flip else pos_pole
+
     fig = go.Figure()
     # Baseline
     x_min, x_max = min(scores) * 1.15, max(scores) * 1.15
+    if x_min == x_max:
+        x_min, x_max = x_min - 1, x_max + 1
     fig.add_trace(
         go.Scatter(
             x=[x_min, x_max],
@@ -297,7 +311,7 @@ def _render_party_axis_chart(
             mode="markers+text",
             text=parties,
             textposition="top center",
-            marker={"size": 12, "color": colours},
+            marker={"size": 18, "color": colours},
             hovertext=hover,
             hoverinfo="text",
             showlegend=False,
@@ -307,12 +321,13 @@ def _render_party_axis_chart(
         height=160,
         margin={"l": 10, "r": 10, "t": 10, "b": 30},
         xaxis={
-            "title": "← Negatieve pool  |  Positieve pool →",
+            "title": f"← {left_label}  |  {right_label} →",
             "zeroline": True,
             "zerolinecolor": "#aaaaaa",
         },
         yaxis={"visible": False, "range": [-1, 2]},
-        plot_bgcolor="white",
+        plot_bgcolor="rgba(0,0,0,0)",
+        paper_bgcolor="rgba(0,0,0,0)",
     )
     st.plotly_chart(fig, use_container_width=True)
 
@@ -784,6 +799,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Breed coalitiebeleid: zorg, defensie, multilateralisme, inclusie",
             "negative_pole": "Radicale PVV-eis tot onmiddellijke uitzetting migranten",
+            "flip": True,
         },
         2: {
             "label": "Nationalistisch migratiebeleid versus progressief internationaal solidariteitsdenken",
@@ -799,6 +815,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Asielbeperking, nationaal belang, restrictief migratiebeleid",
             "negative_pole": "Pro-Palestina, progressieve zorgrechten, anti-discriminatie minderheden",
+            "flip": False,
         },
         3: {
             "label": "Humanitaire solidariteit en inclusie versus nationalistische handhaving en deregulering",
@@ -815,6 +832,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Internationale solidariteit, inclusie en pragmatische overheidsinterventie",
             "negative_pole": "Strikte handhaving, deregulering en nationalistisch eigenbelang boven humanitaire verplichtingen",
+            "flip": True,
         },
         4: {
             "label": "Publieke voorzieningen beschermen versus liberale marktwerking",
@@ -830,8 +848,9 @@ def build_svd_components_tab(db_path: str) -> None:
                 "voorzieningen betaalbaar en toegankelijk te houden, of dat vrije markt en open handel "
                 "leidend moeten zijn."
             ),
-            "positive_pole": "Staatsbescherming van betaalbare publieke voorzieningen voor iedereen",
-            "negative_pole": "Vrije handel, open economie en marktgerichte arbeidsmigratie",
+            "positive_pole": "Vrije handel, open economie en marktgerichte arbeidsmigratie",
+            "negative_pole": "Staatsbescherming van betaalbare publieke voorzieningen voor iedereen",
+            "flip": False,
         },
         5: {
             "label": "Christelijk-conservatief sociaal beleid versus seculier progressief",
@@ -844,8 +863,9 @@ def build_svd_components_tab(db_path: str) -> None:
                 "consistent vanuit een christelijk-sociale visie stemmen tegenover partijen als D66, "
                 "GroenLinks-PvdA en SP die een seculier-progressief beleid voorstaan."
             ),
-            "positive_pole": "Christelijk-conservatief: gezin, kerk, leven, traditionele waarden",
-            "negative_pole": "Seculier-progressief: individuele autonomie, progressieve sociale rechten",
+            "positive_pole": "Seculier-progressief: individuele autonomie, progressieve sociale rechten",
+            "negative_pole": "Christelijk-conservatief: gezin, kerk, leven, traditionele waarden",
+            "flip": True,
         },
         6: {
             "label": "Christelijk-sociaal beschermingsbeleid versus links-progressieve systeemkritiek",
@@ -860,6 +880,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Christelijk-sociaal beschermingsbeleid voor pgb, kinderen en geloofsgroepen",
             "negative_pole": "Links-progressieve systeemkritiek op zorg, arbeid en internationale solidariteit",
+            "flip": False,
         },
         7: {
             "label": "Liberaal investeren en defensie versus linkse bescherming en controle",
@@ -873,6 +894,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Gerichte liberale investeringen in sport, wetenschap en defensie",
             "negative_pole": "Collectieve bescherming, parlementaire controle en anti-marktwerking in zorg",
+            "flip": False,
         },
         8: {
             "label": "Confessioneel-sociaal coalitiebeleid versus procedurele blokkade en handhaving",
@@ -888,6 +910,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Coalitie christelijk-sociaal beleid: defensie, stikstofmaatwerk, bouw en ethiek",
             "negative_pole": "Procedurele blokkade coffeeshop, handhavingsdoelstelling en topsportderegulering",
+            "flip": False,
         },
         9: {
             "label": "Brede coalitiemeerderheid versus links marktingrijpen zorg",
@@ -903,6 +926,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Breed gedragen beleid door centrum-rechts meerderheidsstemmen",
             "negative_pole": "Socialistische inkomensregulering en marktingrijpen in de zorg",
+            "flip": False,
         },
         10: {
             "label": "Gereguleerde kennismigratie en natuur-landbouwtransitie versus institutionele veiligheid",
@@ -918,6 +942,7 @@ def build_svd_components_tab(db_path: str) -> None:
             ),
             "positive_pole": "Beperkte kennismigratie, natuur-landbouwtransitie en Gaza-humanitair",
             "negative_pole": "Institutionele veiligheidssturing, economisch nationalisme en Woo-beperking",
+            "flip": True,
         },
     }
 
@@ -985,7 +1010,7 @@ def build_svd_components_tab(db_path: str) -> None:
 
     # Party axis chart
     party_scores = load_party_axis_scores(db_path)
-    _render_party_axis_chart(party_scores, comp_sel)
+    _render_party_axis_chart(party_scores, comp_sel, theme)
 
     # Batch-fetch motion details (title, date, policy_area, url, body_text, voting_results)
     motion_ids = [m.get("motion_id") for m in motions if m.get("motion_id") is not None]
@@ -1021,21 +1046,28 @@ def build_svd_components_tab(db_path: str) -> None:
     pos_motions = [m for m in motions if float(m.get("score", 0.0)) >= 0]
     neg_motions = [m for m in motions if float(m.get("score", 0.0)) < 0]
 
-    pos_pole = (
-        theme.get("positive_pole", "Positieve pool") if theme else "Positieve pool"
-    )
-    neg_pole = (
-        theme.get("negative_pole", "Negatieve pool") if theme else "Negatieve pool"
-    )
+    flip = theme.get("flip", False) if theme else False
+    pos_pole = theme.get("positive_pole", "") if theme else ""
+    neg_pole = theme.get("negative_pole", "") if theme else ""
+
+    # Determine which pole goes left (progressive) and which goes right
+    if flip:
+        left_pole, right_pole = pos_pole, neg_pole
+        left_motions, right_motions = pos_motions, neg_motions
+        left_arrow, right_arrow = "▲", "▼"
+    else:
+        left_pole, right_pole = neg_pole, pos_pole
+        left_motions, right_motions = neg_motions, pos_motions
+        left_arrow, right_arrow = "▼", "▲"
 
-    pcol, ncol = st.columns(2)
+    lcol, rcol = st.columns(2)
 
-    with pcol:
-        st.success(f"▲ **Positieve pool:** {pos_pole}")
-        for m in pos_motions:
+    with lcol:
+        st.markdown(f"**← {left_pole}**")
+        for m in left_motions:
             mid = m.get("motion_id")
             raw_title = m.get("title") or f"Motie #{mid}"
-            with st.expander(f"▲ {raw_title[:80]}"):
+            with st.expander(f"{left_arrow} {raw_title[:80]}"):
                 row = motion_details.get(int(mid)) if mid is not None else None
                 if row:
                     try:
@@ -1052,12 +1084,12 @@ def build_svd_components_tab(db_path: str) -> None:
                 else:
                     st.caption("_Geen metadata beschikbaar_")
 
-    with ncol:
-        st.error(f"▼ **Negatieve pool:** {neg_pole}")
-        for m in neg_motions:
+    with rcol:
+        st.markdown(f"**{right_pole} →**")
+        for m in right_motions:
             mid = m.get("motion_id")
             raw_title = m.get("title") or f"Motie #{mid}"
-            with st.expander(f"▼ {raw_title[:80]}"):
+            with st.expander(f"{right_arrow} {raw_title[:80]}"):
                 row = motion_details.get(int(mid)) if mid is not None else None
                 if row:
                     try: