Add searchable + faceted History browser (HIST.7)

The History tab was a single flat, time-ordered dropdown with no way to
find a past calculation. Add a client-side search + faceted filter above it.

- Text search by chemical name or formula, type-to-narrow. Name→formula
  resolution (e.g. "benzene" finds C6H6 results) via a new curated
  config.COMMON_NAME_TO_FORMULA map plus exact molecule-library name matches.
  Both sources are precise: synonym/substring matching is deliberately avoided
  so "benzene" can't drag in toluene or ethylbenzene.
- Facet chips/controls for calc type, method, basis, date range, and
  converged status. All facets AND together.
- refresh_results_browser now caches each result's parsed result.json on
  app._history_entries, so filtering re-narrows an in-memory list with no
  per-keystroke disk access. filter_history_entries is a pure function; the
  library/DB lookup for name resolution lives in the impure apply layer.
- Preserves the existing index-0 placeholder + value-preservation contract;
  shows an explicit "no matches" option when every entry is filtered out.

Tests: TestHistoryHardeningHist7 in tests/test_app.py (22 tests) cover the
pure filter across every facet, name→formula resolution (including the
toluene/ethylbenzene false-positive guards), and apply_history_filter
end-to-end.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: NCCU-Schultz-Lab

quantui/app.py

@@ -904,6 +904,13 @@ class QuantUIApp:
         past_dd: Any
         past_output: Any
         past_refresh_btn: Any
+        history_search: Any
+        history_filter_clear_btn: Any
+        history_count_lbl: Any
+        history_method_dd: Any
+        history_basis_dd: Any
+        history_date_from: Any
+        history_date_to: Any
         lib_category_dd: Any
         lib_search_txt: Any
         lib_results_dd: Any
@@ -1788,6 +1795,21 @@ def _wire_callbacks(self) -> None:
         self.past_refresh_btn.on_click(self._on_past_refresh)
         self.copy_path_btn.on_click(self._on_copy_results_path)
         self.view_log_btn.on_click(self._on_view_log)
+        # History search / faceted filters (HIST.7)
+        for _w in (
+            self.history_search,
+            self.history_method_dd,
+            self.history_basis_dd,
+            self.history_date_from,
+            self.history_date_to,
+        ):
+            _w.observe(self._safe_cb(self._on_history_filter_changed), names="value")
+        for _chip in (
+            *self._history_calc_chips.values(),
+            *self._history_status_chips.values(),
+        ):
+            _chip.observe(self._safe_cb(self._on_history_filter_changed), names="value")
+        self.history_filter_clear_btn.on_click(self._on_history_filter_clear)
         # Perf stats reset
         self._reset_btn.on_click(self._on_reset_click)
         self._reset_confirm_yes.on_click(self._on_confirm_yes)
@@ -3512,6 +3534,32 @@ def _on_compare_clear(self, btn) -> None:
     def _on_past_dd_changed(self, change) -> None:
         _hist_on_past_dd_changed(self, change, layout_fn=_layout)
 
+    def _on_history_filter_changed(self, change=None) -> None:
+        from quantui.app_history import apply_history_filter
+
+        apply_history_filter(self)
+
+    def _on_history_filter_clear(self, btn=None) -> None:
+        from quantui.app_history import apply_history_filter
+
+        # Reset every facet widget, suspending the observer so we run a single
+        # filter pass at the end instead of one per widget reset.
+        self._history_filter_suspend = True
+        try:
+            self.history_search.value = ""
+            self.history_method_dd.value = ""
+            self.history_basis_dd.value = ""
+            self.history_date_from.value = None
+            self.history_date_to.value = None
+            for chip in (
+                *self._history_calc_chips.values(),
+                *self._history_status_chips.values(),
+            ):
+                chip.value = False
+        finally:
+            self._history_filter_suspend = False
+        apply_history_filter(self)
+
     def _on_past_refresh(self, btn) -> None:
         self._activity_begin("Refreshing history list...")
         try:

quantui/app_builders.py

@@ -430,15 +430,116 @@ def build_history_section(
     app._cal_accordion = widgets.Accordion(children=[cal_panel], selected_index=None)
     app._cal_accordion.set_title(0, "Calibrate time estimates")
 
+    # ── Search / faceted filters (HIST.7) ──────────────────────────────
+    # All filtering is client-side over the cached ``app._history_entries``
+    # list; widgets here only hold facet state. See app_history.apply_history_filter.
+    from quantui.app_history import HISTORY_CALC_TYPE_FACETS, HISTORY_STATUS_FACETS
+
+    app._history_entries = []
+    app._history_filter_suspend = False
+    app.history_search = widgets.Text(
+        placeholder="search name or formula (e.g. benzene, C6H6)",
+        continuous_update=True,  # type-to-narrow
+        layout=layout_fn(width="300px"),
+    )
+    app.history_filter_clear_btn = widgets.Button(
+        icon="times",
+        tooltip="Clear all history filters",
+        layout=layout_fn(width="40px"),
+    )
+    app.history_count_lbl = widgets.HTML(
+        '<span style="color:#888;font-size:12px"></span>'
+    )
+    app._history_calc_chips = {
+        key: widgets.ToggleButton(
+            value=False,
+            description=label,
+            tooltip=f"Show only {label} calculations",
+            layout=layout_fn(width="auto"),
+        )
+        for label, key in HISTORY_CALC_TYPE_FACETS
+    }
+    app.history_method_dd = widgets.Dropdown(
+        options=[("Any method", "")],
+        value="",
+        description="Method:",
+        style={"description_width": "55px"},
+        layout=layout_fn(width="200px"),
+    )
+    app.history_basis_dd = widgets.Dropdown(
+        options=[("Any basis", "")],
+        value="",
+        description="Basis:",
+        style={"description_width": "55px"},
+        layout=layout_fn(width="200px"),
+    )
+    app.history_date_from = widgets.DatePicker(
+        description="From:",
+        style={"description_width": "45px"},
+        layout=layout_fn(width="200px"),
+    )
+    app.history_date_to = widgets.DatePicker(
+        description="To:",
+        style={"description_width": "35px"},
+        layout=layout_fn(width="190px"),
+    )
+    app._history_status_chips = {
+        key: widgets.ToggleButton(
+            value=False,
+            description=label,
+            layout=layout_fn(width="auto"),
+        )
+        for label, key in HISTORY_STATUS_FACETS
+    }
+
+    def _facet_label(text: str, width: str = "60px") -> widgets.HTML:
+        return widgets.HTML(
+            f'<span style="color:#555;font-size:12px;width:{width};'
+            f'display:inline-block">{text}</span>'
+        )
+
+    app._history_filter_box = widgets.VBox(
+        [
+            widgets.HBox(
+                [
+                    app.history_search,
+                    app.history_filter_clear_btn,
+                    app.history_count_lbl,
+                ],
+                layout=layout_fn(align_items="center", gap="6px"),
+            ),
+            widgets.HBox(
+                [_facet_label("Type:"), *app._history_calc_chips.values()],
+                layout=layout_fn(align_items="center", gap="4px", flex_wrap="wrap"),
+            ),
+            widgets.HBox(
+                [app.history_method_dd, app.history_basis_dd],
+                layout=layout_fn(align_items="center", gap="8px"),
+            ),
+            widgets.HBox(
+                [
+                    app.history_date_from,
+                    app.history_date_to,
+                    _facet_label("Status:", "55px"),
+                    *app._history_status_chips.values(),
+                ],
+                layout=layout_fn(align_items="center", gap="6px", flex_wrap="wrap"),
+            ),
+        ],
+        layout=layout_fn(margin="0 0 8px", gap="4px"),
+    )
+
     # The History tab is now purely the result-browser. Performance stats
     # + Calibrate accordions moved to the System Settings tab — see below —
     # so the user finds benchmarking + system state in one logical place.
     app.history_panel = widgets.VBox(
         [
             widgets.HTML(
                 '<p style="color:#555;font-size:13px;margin:0 0 8px">'
-                "Calculations are saved automatically. Select one below to view its results.</p>"
+                "Calculations are saved automatically. Filter below, then select "
+                "one to view its results.</p>"
             ),
+            app._history_filter_box,
             widgets.HBox(
                 [
                     app.past_dd,