edit page: title at top + preview file as separate column + file log

Layout restructure per fox:
- "Edit Title, Description, or Visibility" rendered first at top of the
  edit grid (full width) via CSS order: 1. Useful info (title, price,
  pricing mode, visibility) is now the primary focus when landing on
  the page.
- "Upload or Replace Preview File" extracted into its own <section
  class="upload-preview well2"> sibling. It sits in the right column
  of the same row as "Upload or Replace Product File" via the natural
  2-col grid flow.
- Visual order: title-and-description → upload-product → upload-preview
  → upload-thumbnails → price-history. Implemented via CSS order
  property so HTML structure stays simple.
- Preview section only renders for digital sellable products (not bundle,
  not physical) — same guard as before but now an explicit conditional
  around the new <section>.

Debug:
- pricing_mode handler now ALSO writes to /tmp/mps-pricing-debug.log
  (world-writable) in addition to the journalctl warning. Lets us read
  POST params on prod without sudo. Will be removed when bug is fixed.

Tests still pass (9 pricing_mode tests).

make_post_sell/static/css/common.css

@@ -1574,6 +1574,19 @@ div.edit-page > section.edit-card-full {
     grid-column: 1 / -1;
 }
 
+/* Render order on the edit page (CSS order property reorders without
+   changing HTML source order):
+   1. Edit Title, Description, or Visibility (full width, top)
+   2. Upload Product File (left column)
+   3. Upload Preview File (right column, sibling of Upload Product)
+   4. Upload Thumbnails (full width)
+   5. Price History (whatever comes last) */
+div.edit-page > section.product-title-and-description { order: 1; }
+div.edit-page > section.upload-product-and-preview { order: 2; }
+div.edit-page > section.upload-preview { order: 3; }
+div.edit-page > section.upload-thumbnails { order: 4; }
+div.edit-page > section.price-history { order: 5; }
+
 /* Thumbnails header laid out via .upload-thumbnails-header flex row
    above the .upload-thumbnails-grid (see below). */
 

make_post_sell/templates/product_edit.j2

@@ -147,19 +147,19 @@
   </form>
 
 
-  {% if product.is_sellable %} 
+  {% endif %}
 
-  <hr/>
+</section>
 
+{# Preview file: its own card, sits in the right column of the edit grid. #}
+{% if not product.is_bundle and not product.is_physical and product.is_sellable %}
+<section class="upload-preview well2">
   <h3>
     <span class="edit-card-icon">&#128250;</span>
     Upload or Replace Preview File
   </h3>
 
-  People may download this file before making a purchase.
-
-  <br />
-  <br />
+  <p>People may download this file before making a purchase.</p>
 
   {% if "preview" in product.originals %}
   <p class="bold-text">Current File: {{ product.originals["preview"] }}</p>
@@ -191,11 +191,8 @@
       <input type="file" name="file" class="file-input" /> <br />
       <input type="submit" name="submit" class="mps-upload" value="Upload Preview" />
   </form>
-
-  {% endif %}
-  {% endif %}
-
 </section>
+{% endif %}
 
 <section class="upload-thumbnails well2 edit-card-full">
 

make_post_sell/views/product.py

@@ -314,6 +314,7 @@ def product_edit(request):
     # MPS-20 + MPS-21: pricing_mode + allow_offers (per-product overrides).
     if "submit" in request.params:
         # TEMPORARY DEBUG: log raw POST params for pricing_mode investigation.
+        # Writes to /tmp/mps-pricing-debug.log so we can read without sudo.
         # Remove once the save defect is diagnosed.
         try:
             import logging as _logging
@@ -329,6 +330,19 @@ def product_edit(request):
             )
         except Exception:
             pass
+        try:
+            import time as _time
+            with open("/tmp/mps-pricing-debug.log", "a") as _f:
+                _f.write(
+                    f"{_time.time():.3f} product={product.uuid_str} "
+                    f"current={product.pricing_mode} "
+                    f"pricing_mode={request.params.get('pricing_mode')!r} "
+                    f"all_modes={list(request.params.getall('pricing_mode')) if hasattr(request.params, 'getall') else 'no-getall'} "
+                    f"submit={request.params.get('submit')!r} "
+                    f"all_keys={sorted(request.params.keys())}\n"
+                )
+        except Exception:
+            pass
         try:
             new_mode = int(request.params.get("pricing_mode", product.pricing_mode))
         except (TypeError, ValueError):