ProvidersStep search: tighten icons, commit-to-chip, primary search button

Sticky search now uses Autocomplete (multiple+freeSolo capped to 1)
instead of a plain TextField:
- Pin icon tightened to the left edge and to the placeholder
- Committed location renders inside the input as an FA Chip with an
  X delete (clears the committed filter)
- Primary-coloured magnifying-glass IconButton on the right commits
  the draft; disabled while the draft is empty
- Typing no longer filters live — Enter or the search button promotes
  the draft to a chip, matching the chip mental model

The FilterPanel dialog's Location autocomplete already read from the
same searchQuery state, so it continues to display the committed chip.

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

src/components/pages/ProvidersStep/ProvidersStep.tsx

@@ -10,6 +10,7 @@ import Menu from '@mui/material/Menu';
 import ToggleButtonGroup from '@mui/material/ToggleButtonGroup';
 import ToggleButton from '@mui/material/ToggleButton';
 import SwapVertIcon from '@mui/icons-material/SwapVert';
+import SearchIcon from '@mui/icons-material/Search';
 import ViewListOutlinedIcon from '@mui/icons-material/ViewListOutlined';
 import MapOutlinedIcon from '@mui/icons-material/MapOutlined';
 import LocationOnOutlinedIcon from '@mui/icons-material/LocationOnOutlined';
@@ -19,6 +20,7 @@ import { ProviderCard } from '../../molecules/ProviderCard';
 import { FilterPanel } from '../../molecules/FilterPanel';
 import { Button } from '../../atoms/Button';
 import { Chip } from '../../atoms/Chip';
+import { IconButton } from '../../atoms/IconButton';
 import { Switch } from '../../atoms/Switch';
 import { Typography } from '../../atoms/Typography';
 import { Divider } from '../../atoms/Divider';
@@ -246,6 +248,18 @@ export const ProvidersStep: React.FC<ProvidersStepProps> = ({
 
   // ─── Local state ───
   const [sortAnchor, setSortAnchor] = React.useState<null | HTMLElement>(null);
+  // Draft value for the sticky search input — only committed (promoted to a
+  // chip) on Enter or when the search button is clicked. searchQuery is the
+  // committed filter value; the draft lives here until the user confirms.
+  const [searchDraft, setSearchDraft] = React.useState('');
+
+  const commitSearch = (next: string) => {
+    const trimmed = next.trim();
+    if (!trimmed) return;
+    onSearchChange(trimmed);
+    onSearch?.(trimmed);
+    setSearchDraft('');
+  };
 
   // ─── Price input local state (commits on blur / Enter) ───
   const [priceMinInput, setPriceMinInput] = React.useState(String(filterValues.priceRange[0]));
@@ -395,27 +409,82 @@ export const ProvidersStep: React.FC<ProvidersStepProps> = ({
           borderColor: 'divider',
         }}
       >
-        {/* Location search */}
-        <TextField
-          placeholder="Search a town or suburb..."
-          aria-label="Search providers by town or suburb"
-          value={searchQuery}
-          onChange={(e) => onSearchChange(e.target.value)}
-          onKeyDown={(e) => {
-            if (e.key === 'Enter' && onSearch) {
-              e.preventDefault();
-              onSearch(searchQuery);
-            }
+        {/* Location search — committed location renders as a chip inside the
+            input. Typing produces a draft; Enter or the search button commit
+            it. Deleting the chip clears the committed filter. */}
+        <Autocomplete
+          multiple
+          freeSolo
+          options={[]}
+          value={searchQuery.trim() ? [searchQuery.trim()] : []}
+          inputValue={searchDraft}
+          onInputChange={(_, newDraft, reason) => {
+            // Ignore the 'reset' input-change Autocomplete fires after a value
+            // commit (it echoes the committed value back into the input and
+            // would otherwise re-populate the draft we just cleared).
+            if (reason === 'reset') return;
+            setSearchDraft(newDraft);
           }}
-          fullWidth
+          onChange={(_, newValue) => {
+            if (newValue.length === 0) {
+              // Chip removed — clear the committed filter
+              onSearchChange('');
+              return;
+            }
+            // Commit the most-recent entry (cap at 1 location)
+            const last = newValue[newValue.length - 1];
+            if (typeof last === 'string') commitSearch(last);
+          }}
+          renderTags={(value, getTagProps) =>
+            value.map((option, index) => {
+              const { key, ...chipProps } = getTagProps({ index });
+              return (
+                <Chip
+                  key={key}
+                  label={option}
                   size="small"
+                  selected
+                  aria-label={`Current location: ${option}. Press delete to clear.`}
+                  {...chipProps}
+                />
+              );
+            })
+          }
+          renderInput={(params) => (
+            <TextField
+              {...params}
+              placeholder={searchQuery.trim() ? '' : 'Search a town or suburb...'}
+              size="small"
+              inputProps={{
+                ...params.inputProps,
+                'aria-label': 'Search providers by town or suburb',
+              }}
               InputProps={{
+                ...params.InputProps,
                 startAdornment: (
-              <InputAdornment position="start">
+                  <>
+                    <InputAdornment position="start" sx={{ ml: 0.5, mr: 0.5 }}>
                       <LocationOnOutlinedIcon sx={{ color: 'text.secondary', fontSize: 20 }} />
                     </InputAdornment>
+                    {params.InputProps.startAdornment}
+                  </>
+                ),
+                endAdornment: (
+                  <InputAdornment position="end" sx={{ mr: 0.25 }}>
+                    <IconButton
+                      aria-label="Search"
+                      color="primary"
+                      size="small"
+                      onClick={() => commitSearch(searchDraft)}
+                      disabled={!searchDraft.trim()}
+                    >
+                      <SearchIcon fontSize="small" />
+                    </IconButton>
+                  </InputAdornment>
                 ),
               }}
+            />
+          )}
           sx={{ mb: 1.5 }}
         />