fix(admin): protect cornerstone .md files from bulk delete + fix PDF 500

- Bulk delete (both explicit-IDs and apply_to_all paths) now only unlinks
  source .md files for generated articles (template_slug IS NOT NULL).
  Manual cornerstone articles keep their .md source on disk.

- _sync_static_articles() now also renders markdown → HTML and writes to
  BUILD_DIR/<lang>/<slug>.html after upserting the DB row, so cornerstones
  are immediately servable after a sync without a separate rebuild step.

- scenario_pdf(): replace d = json.loads(scenario["calc_json"]) with
  d = calc(state) so all current calc fields (moic, dscr, cashOnCash, …)
  are present and the PDF route no longer 500s on stale stored JSON.

- Restored data/content/articles/ cornerstone .md files via git checkout.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/src/padelnomics/admin/routes.py

@@ -2142,7 +2142,7 @@ async def scenario_preview(scenario_id: int):
 async def scenario_pdf(scenario_id: int):
     """Generate and immediately download a business plan PDF for a published scenario."""
     from ..businessplan import get_plan_sections
-    from ..planner.calculator import validate_state
+    from ..planner.calculator import calc, validate_state
 
     scenario = await fetch_one("SELECT * FROM published_scenarios WHERE id = ?", (scenario_id,))
     if not scenario:
@@ -2153,7 +2153,7 @@ async def scenario_pdf(scenario_id: int):
         lang = "en"
 
     state = validate_state(json.loads(scenario["state_json"]))
-    d = json.loads(scenario["calc_json"])
+    d = calc(state)
     sections = get_plan_sections(state, d, lang)
     sections["scenario_name"] = scenario["title"]
     sections["location"] = scenario.get("location", "")
@@ -2274,6 +2274,18 @@ async def _sync_static_articles() -> None:
              template_slug, group_key, now_iso, now_iso),
         )
 
+        # Build HTML so the article is immediately servable (cornerstones have no template)
+        if template_slug is None:
+            from ..content.routes import BUILD_DIR, bake_product_cards, bake_scenario_cards
+
+            body = raw[m.end():]
+            body_html = mistune.html(body)
+            body_html = await bake_scenario_cards(body_html, lang=language)
+            body_html = await bake_product_cards(body_html, lang=language)
+            build_dir = BUILD_DIR / language
+            build_dir.mkdir(parents=True, exist_ok=True)
+            (build_dir / f"{slug}.html").write_text(body_html)
+
 
 def _build_article_where(
     status: str = None,
@@ -2601,12 +2613,15 @@ async def articles_bulk():
             from ..content.routes import BUILD_DIR
 
             rows = await fetch_all(
-                f"SELECT id, slug FROM articles WHERE {where} LIMIT 5000", tuple(where_params)
+                f"SELECT id, slug, template_slug FROM articles WHERE {where} LIMIT 5000",
+                tuple(where_params),
             )
             for a in rows:
                 build_path = BUILD_DIR / f"{a['slug']}.html"
                 if build_path.exists():
                     build_path.unlink()
+                # Only remove source .md for generated articles; cornerstones have no template
+                if a["template_slug"] is not None:
                     md_path = Path("data/content/articles") / f"{a['slug']}.md"
                     if md_path.exists():
                         md_path.unlink()
@@ -2655,13 +2670,15 @@ async def articles_bulk():
             from ..content.routes import BUILD_DIR
 
             articles_rows = await fetch_all(
-                f"SELECT id, slug FROM articles WHERE id IN ({placeholders})",
+                f"SELECT id, slug, template_slug FROM articles WHERE id IN ({placeholders})",
                 tuple(article_ids),
             )
             for a in articles_rows:
                 build_path = BUILD_DIR / f"{a['slug']}.html"
                 if build_path.exists():
                     build_path.unlink()
+                # Only remove source .md for generated articles; cornerstones have no template
+                if a["template_slug"] is not None:
                     md_path = Path("data/content/articles") / f"{a['slug']}.md"
                     if md_path.exists():
                         md_path.unlink()