docs+code: rename tool labels everywhere

Sweep follow-up to 93e43fc. Display labels now consistent across docs,
landing pages, CLI output, code comments, docstrings, and test prose.
Five parallel surfaces touched:

- docs (EN + ES): README, USER-GUIDE, CLI-REFERENCE, and 11 internal
  design/planning docs
- landing pages: index + bookkeeper/revops/shopify-pet
- src: CLI module docstrings, _TOOL_DISPLAY dicts in cli_analyze.py
  and gui/components/_legacy.py, core module headers, every tool
  page's module docstring
- tests: class/method/module docstrings and section-header comments
- test-cases READMEs

Page slugs (1_Deduplicator etc.), tool_id strings (01_deduplicator
etc.), Python class names (TestDeduplicatorWorkflow, FeatureFlag.*),
URL paths, anchor IDs, CSS classes, and asset filenames were left
intact since they're code identifiers / structural references.

All 2033 tests pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/gui/__init__.py

@@ -1 +1 @@
-"""Streamlit GUI for the DataTools Deduplicator."""
+"""Streamlit GUI for DataTools."""

src/gui/components/__init__.py

@@ -16,7 +16,7 @@ they need without dragging the entire kitchen-sink module:
         dedup_review.py    ← dedup match-group cards + review pipeline
         shared.py          ← chrome / file-pickup helpers used by every tool
 
-A standalone Deduplicator build, for example, can ship without
+A standalone Find Duplicates build, for example, can ship without
 ``findings.py`` and ``gate.py`` — those modules import the analyzer /
 gate code that the Lite SKU does not include.
 

src/gui/components/_legacy.py

@@ -847,15 +847,15 @@ def _build_match_groups_csv(
 # Tool id -> friendly display name. Single source of truth for the GUI; the
 # CLI keeps its own copy so each entrypoint stays self-contained.
 TOOL_DISPLAY_NAMES: dict[str, str] = {
-    "01_deduplicator": "Deduplicator",
-    "02_text_cleaner": "Text Cleaner",
-    "03_format_standardizer": "Format Standardizer",
-    "04_missing_handler": "Missing Value Handler",
-    "05_column_mapper": "Column Mapper",
-    "06_outlier_detector": "Outlier Detector",
-    "07_multi_file_merger": "Multi-File Merger",
-    "08_validator_reporter": "Validator & Reporter",
-    "09_pipeline_runner": "Pipeline Runner",
+    "01_deduplicator": "Find Duplicates",
+    "02_text_cleaner": "Clean Text",
+    "03_format_standardizer": "Standardize Formats",
+    "04_missing_handler": "Fix Missing Values",
+    "05_column_mapper": "Map Columns",
+    "06_outlier_detector": "Find Unusual Values",
+    "07_multi_file_merger": "Combine Files",
+    "08_validator_reporter": "Quality Check",
+    "09_pipeline_runner": "Automated Workflows",
 }
 
 _SEVERITY_ICON: dict[str, str] = {
@@ -1016,7 +1016,7 @@ def render_hidden_aware_preview(
 ) -> None:
     """Render a DataFrame preview that shows hidden characters in every cell.
 
-    Used for the Text Cleaner's "before" and "after" previews so the user
+    Used for the Clean Text tool's "before" and "after" previews so the user
     can actually see the leading/trailing whitespace, NBSP padding,
     zero-width characters, and smart punctuation that the cleaner is going
     to remove (or just removed). A plain ``st.dataframe`` collapses outer

src/gui/pages/1_Deduplicator.py

@@ -1,4 +1,4 @@
-"""DataTools Deduplicator — full working tool page."""
+"""DataTools Find Duplicates — full working tool page."""
 
 from __future__ import annotations
 

src/gui/pages/2_Text_Cleaner.py

@@ -1,4 +1,4 @@
-"""DataTools Text Cleaner — Streamlit page."""
+"""DataTools Clean Text — Streamlit page."""
 
 from __future__ import annotations
 

src/gui/pages/3_Format_Standardizer.py

@@ -1,4 +1,4 @@
-"""DataTools Format Standardizer — Streamlit page."""
+"""DataTools Standardize Formats — Streamlit page."""
 
 from __future__ import annotations
 

src/gui/pages/4_Missing_Values.py

@@ -1,4 +1,4 @@
-"""DataTools Missing Value Handler — Streamlit page."""
+"""DataTools Fix Missing Values — Streamlit page."""
 
 from __future__ import annotations
 

src/gui/pages/5_Column_Mapper.py

@@ -1,4 +1,4 @@
-"""DataTools Column Mapper — Streamlit page."""
+"""DataTools Map Columns — Streamlit page."""
 
 from __future__ import annotations
 

src/gui/pages/6_Outlier_Detector.py

@@ -1,4 +1,4 @@
-"""DataTools Outlier Detector — stub page."""
+"""DataTools Find Unusual Values — stub page."""
 
 from __future__ import annotations
 

src/gui/pages/7_Multi_File_Merger.py

@@ -1,4 +1,4 @@
-"""DataTools Multi-File Merger — stub page."""
+"""DataTools Combine Files — stub page."""
 
 from __future__ import annotations
 

src/gui/pages/8_Validator_Reporter.py

@@ -1,4 +1,4 @@
-"""DataTools Validator & Reporter — stub page."""
+"""DataTools Quality Check — stub page."""
 
 from __future__ import annotations
 

src/gui/pages/9_Pipeline_Runner.py

@@ -1,4 +1,4 @@
-"""DataTools Pipeline Runner — Streamlit page."""
+"""DataTools Automated Workflows — Streamlit page."""
 
 from __future__ import annotations