feat(layout-review): address review findings on pages 7-12

Find Duplicates (01_deduplicator):
- Delete the redundant outer Options wrapper; surface threshold +
  survivor rule directly, push the rest behind a single Advanced pane.
- Disambiguate competing primaries: top result is an auto-resolved
  preview (secondary download), review decisions are the single primary.
- Plain-English match labels (exact / approximate); clarify the third.
- Lift the match-card caption to a one-time instruction; note delimiter
  is delimited-text-only.

Quality Check (08_validator_reporter) — stub:
- Remove the dead disabled "Load rules file (JSON)" uploader so the
  stub invites a single action; keep the informative feature list.

Map Columns (05_column_mapper):
- Regroup schema -> mapping -> strategy/advanced (core task contiguous).
- Make preset-vs-Advanced precedence legible (Custom + modified marker).
- Adopt the compact file-intake banner; drop the duplicate resolved-
  mapping table; fix the add-row gutter style.

Combine Files (07_multi_file_merger) — stub:
- Actually disable the Merge CTA (add the disabled attribute).

PDF to CSV (10_pdf_extractor):
- Drop page/raw from the default preview to match export + fix the
  horizontal clip; surface raw via per-row affordance + overflow-x.
- Move the column selector above the download button; give auto-excluded
  rows a reason; align the files card to Home; de-dupe the row count.

Automated Workflows (09_pipeline_runner):
- Replace hand-edited JSON step config with per-step control expanders;
  JSON moved behind Advanced import/export.
- Editing the table marks the mode modified; fold the empty error column
  into the status pill; render summaries as plain English; collapse the
  explainer by default.

Cross-cutting items (stub standardization on page 10, shared disabled-
field token, remaining intake rollout) deferred to a holistic pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

layout-review/05_column_mapper.html

@@ -25,22 +25,12 @@
 
       <div class="dt-spacer"></div>
 
-      <!-- Upload (file staged) -->
-      <p class="dt-caption">You can also import a file on the home screen and pick it up here.</p>
-      <label class="dt-label">Import CSV or Excel file</label>
-      <div class="dt-uploader">
-        <div class="dt-uploader-text">
-          <span class="hint"><span class="dt-mi" style="vertical-align:-4px">upload_file</span> Drag and drop file here</span>
-          <span class="sub">Up to 1.5 GB · CSV, TSV, XLSX, XLS · encoding &amp; delimiter auto-detected</span>
-        </div>
-        <button class="dt-btn">Browse files</button>
-      </div>
-      <div class="dt-file-chip">
-        <span class="dt-file-icon-chip"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor"><path d="M14 2H6a2 2 0 00-2 2v16a2 2 0 002 2h12a2 2 0 002-2V8z"/><path d="M14 2v6h6"/></svg></span>
-        <span class="name">crm_contacts_raw.csv</span>
-        <span class="size">684 KB</span>
-        <button class="dt-btn dt-btn-tertiary" title="Remove">✕</button>
+      <!-- File pickup banner (using file from upload screen) -->
+      <div class="dt-alert info">
+        <span class="dt-mi">description</span>
+        <span>Using <strong>crm_contacts_raw.csv</strong> from the upload screen.</span>
       </div>
+      <button class="dt-btn" style="margin-bottom:4px">Use a different file</button>
 
       <!-- Preview expander (collapsed after a result exists) -->
       <details class="dt-expander">
@@ -93,7 +83,7 @@
                 <tr><td>signup_date</td><td>date</td><td>✗</td><td></td><td>Signup</td></tr>
                 <tr><td>amount_spent</td><td>float</td><td>✗</td><td>0.0</td><td>Amount Spent</td></tr>
                 <tr><td>source</td><td>string</td><td>✗</td><td>crm-import</td><td></td></tr>
-                <tr><td class="idx" style="color:var(--ink-tertiary)"><span class="dt-mi" style="font-size:16px;vertical-align:-3px">add</span> add row</td><td></td><td></td><td></td><td></td></tr>
+                <tr><td style="color:var(--ink-tertiary)"><span class="dt-mi" style="font-size:16px;vertical-align:-3px">add</span> add row</td><td></td><td></td><td></td><td></td></tr>
               </tbody>
             </table>
           </div>
@@ -101,43 +91,8 @@
 
           <hr class="dt-divider">
 
-          <!-- ===== Strategy ===== -->
-          <h3>Strategy</h3>
-          <div class="dt-field">
-            <label class="dt-label">Preset</label>
-            <div class="dt-radio-row" style="flex-direction:column; gap:8px">
-              <span class="dt-radio"><span class="dot"></span> rename-only (just rename, leave types alone, keep extras)</span>
-              <span class="dt-radio on"><span class="dot"></span> lenient-schema (rename + coerce + reorder, keep extras)</span>
-              <span class="dt-radio"><span class="dot"></span> strict-schema (rename + coerce + reorder, drop extras)</span>
-            </div>
-          </div>
-
-          <!-- Advanced options expander -->
-          <details class="dt-expander">
-            <summary>Advanced options</summary>
-            <div class="dt-expander-body">
-              <div class="dt-cols-2">
-                <div>
-                  <div class="dt-field">
-                    <label class="dt-label">Unmapped source columns</label>
-                    <div class="dt-select">keep</div>
-                  </div>
-                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Coerce types per schema</div>
-                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Reorder to schema order</div>
-                </div>
-                <div>
-                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Auto-infer mapping (fuzzy match)</div>
-                  <div class="dt-field">
-                    <label class="dt-label">Fuzzy match threshold</label>
-                    <div class="dt-slider"><div class="track"><div class="fill" style="width:80%"></div><div class="knob" style="left:80%"></div></div><div class="val">0.80</div></div>
-                  </div>
-                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Enforce required fields</div>
-                </div>
-              </div>
-            </div>
-          </details>
-
           <!-- ===== Mapping ===== -->
+          <!-- Mapping follows the schema directly: define the schema, then map sources onto it. -->
           <h3>Mapping</h3>
           <!-- schema is set → source→target selectbox editor with auto-suggested flag -->
           <div class="dt-table-wrap">
@@ -153,7 +108,53 @@
               </tbody>
             </table>
           </div>
-          <p class="dt-caption">Pick a target for each source column. <code>Notes</code> stays unmapped — with the lenient preset it is kept as-is. <code>source</code> is added from the schema default.</p>
+          <p class="dt-caption">Pick a target for each source column. <code>Notes</code> stays unmapped — with the keep-extras strategy it is kept as-is. <code>source</code> is added from the schema default.</p>
+
+          <hr class="dt-divider">
+
+          <!-- ===== Strategy ===== -->
+          <!-- Strategy is a modifier on the mapping above (strictness: keep/drop extras, coerce, reorder), so it comes after the user can see what it acts on. -->
+          <h3>Strategy</h3>
+          <div class="dt-field">
+            <label class="dt-label">Preset</label>
+            <div class="dt-radio-row" style="flex-direction:column; gap:8px">
+              <span class="dt-radio"><span class="dot"></span> rename-only (just rename, leave types alone, keep extras)</span>
+              <span class="dt-radio"><span class="dot"></span> lenient-schema (rename + coerce + reorder, keep extras)</span>
+              <span class="dt-radio"><span class="dot"></span> strict-schema (rename + coerce + reorder, drop extras) <span class="dt-count-pill info" style="margin-left:4px">base</span></span>
+              <span class="dt-radio on"><span class="dot"></span> Custom — based on <strong>strict-schema</strong>, 1 control changed <span class="dt-count-pill warn" style="margin-left:4px">modified</span></span>
+            </div>
+            <div class="dt-precedence" style="margin-top:10px">
+              <span class="dt-mi">rule</span>
+              <span>Individual Advanced controls win over the preset. You started from <strong>strict-schema</strong>, then changed <strong>Unmapped source columns</strong> to <strong>keep</strong> below — so the preset is now <strong>Custom</strong>. The controls' current values are what actually run.</span>
+            </div>
+            <div class="dt-help-text">Pick a strategy as the baseline. Every Advanced toggle below is still individually overridable; overriding any one switches the preset to Custom.</div>
+          </div>
+
+          <!-- Advanced options expander -->
+          <details class="dt-expander" open>
+            <summary>Advanced options</summary>
+            <div class="dt-expander-body">
+              <div class="dt-cols-2">
+                <div>
+                  <div class="dt-field">
+                    <label class="dt-label">Unmapped source columns <span class="dt-count-pill warn" style="margin-left:4px">changed</span></label>
+                    <div class="dt-select">keep</div>
+                    <div class="dt-help-text">Winning value: <strong>keep</strong>. Overrides the strict-schema base (drop) — so <code>Notes</code> survives into the output.</div>
+                  </div>
+                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Coerce types per schema</div>
+                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Reorder to schema order</div>
+                </div>
+                <div>
+                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Auto-infer mapping (fuzzy match)</div>
+                  <div class="dt-field">
+                    <label class="dt-label">Fuzzy match threshold</label>
+                    <div class="dt-slider"><div class="track"><div class="fill" style="width:80%"></div><div class="knob" style="left:80%"></div></div><div class="val">0.80</div></div>
+                  </div>
+                  <div class="dt-check on"><span class="box"><span class="dt-mi">check</span></span> Enforce required fields</div>
+                </div>
+              </div>
+            </div>
+          </details>
 
         </div>
       </details>
@@ -176,20 +177,6 @@
       <div class="dt-alert info"><span class="dt-mi">info</span><span>Added (with defaults): <code>source</code></span></div>
       <div class="dt-alert warn"><span class="dt-mi">warning</span><span>Some cells could not be coerced and were left as NaN: amount_spent (3)</span></div>
 
-      <p><strong>Resolved mapping</strong></p>
-      <div class="dt-table-wrap">
-        <table class="dt-table">
-          <thead><tr><th>source</th><th>target</th><th>auto</th></tr></thead>
-          <tbody>
-            <tr><td>Full Name</td><td>full_name</td><td>True</td></tr>
-            <tr><td>EmailAddr</td><td>email</td><td>True</td></tr>
-            <tr><td>Phone #</td><td>phone</td><td>True</td></tr>
-            <tr><td>Signup</td><td>signup_date</td><td>True</td></tr>
-            <tr><td>Amount Spent</td><td>amount_spent</td><td>True</td></tr>
-          </tbody>
-        </table>
-      </div>
-
       <p><strong>Mapped preview (first 10 rows)</strong></p>
       <div class="dt-table-wrap">
         <table class="dt-table">