feat(studio): clearer store + channel switcher + approvals & welcome polish

- store: repair the filter dialog crash (a Spacer lived directly in
  AlertDialog.actions, which is an OverflowBar, not a Flex — it threw
  and rendered a broken dialog). Buttons now sit in a Row.
- store: promote the module-store manager from a bare icon to a
  labelled 'Add store' button, and fully localize the dialog (DE/EN).
- store: add a curated 'Suggested stores' shelf with one-click
  add/remove (first entry: Recl∆Im). Each suggestion is probed for
  reachability and shows 'not available yet' until its index is
  published, instead of failing only on click. Fail-open on network
  errors so a transient hiccup never hides a real store.
- sidebar: the channel pill is now a one-click channel switcher
  (menu with per-channel running state + active check; switching
  writes ~/.chain/current-channel, restarts the daemon, and Studio
  repoints to the new channel).
- approvals: lead the card with the human prompt ('what am I
  releasing?') and demote the flow/step id to a metadata line; clear
  fallback when the step left the prompt empty.
- welcome: tidy the docs grid into equal-height paired rows with a
  full-width trailing card for the odd one out.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/pages/approvals.dart

@@ -527,6 +527,9 @@ class _ApprovalCard extends StatelessWidget {
       child: Column(
         crossAxisAlignment: CrossAxisAlignment.start,
         children: [
+          // Status row: selection + state + expiry. No flow id here —
+          // the headline below leads with WHAT is being asked, not the
+          // technical flow name.
           Row(
             children: [
               Checkbox(
@@ -540,15 +543,7 @@ class _ApprovalCard extends StatelessWidget {
                 tone: ChainPillTone.warning,
                 icon: Icons.pending_outlined,
               ),
-              const SizedBox(width: ChainSpace.sm),
-              Expanded(
-                child: Text(
-                  '${approval.flowName} › ${approval.stepId}',
-                  style: theme.textTheme.titleMedium?.copyWith(
-                    fontWeight: FontWeight.w600,
-                  ),
-                ),
-              ),
+              const Spacer(),
               if (approval.expiresAt != null)
                 ChainPill(
                   label: _expiresInLabel(context, approval.expiresAt!),
@@ -558,7 +553,38 @@ class _ApprovalCard extends StatelessWidget {
             ],
           ),
           const SizedBox(height: ChainSpace.lg),
-          Text(approval.prompt, style: theme.textTheme.bodyLarge),
+          // Headline = the human question the flow author wrote ("what
+          // am I approving"). Falls back to a clear sentence when the
+          // step left the prompt empty, so the card is never reduced to
+          // a cryptic flow id.
+          Text(
+            approval.prompt.trim().isEmpty
+                ? l.approvalsRequestFallback
+                : approval.prompt,
+            style: theme.textTheme.titleMedium?.copyWith(
+              fontWeight: FontWeight.w600,
+            ),
+          ),
+          const SizedBox(height: 4),
+          // Technical context, demoted to a small metadata line.
+          Row(
+            children: [
+              Icon(
+                Icons.account_tree_outlined,
+                size: 13,
+                color: theme.colorScheme.onSurfaceVariant,
+              ),
+              const SizedBox(width: 6),
+              Expanded(
+                child: Text(
+                  l.approvalsFlowStepMeta(approval.flowName, approval.stepId),
+                  style: theme.textTheme.bodySmall?.copyWith(
+                    color: theme.colorScheme.onSurfaceVariant,
+                  ),
+                ),
+              ),
+            ],
+          ),
           if (approval.payloadPreview != null) ...[
             const SizedBox(height: ChainSpace.md),
             Padding(

lib/pages/store.dart

@@ -234,10 +234,15 @@ class _StorePageState extends State<StorePage> {
               onPressed: _openFilterDialog,
             ),
           ),
-          IconButton(
-            icon: const Icon(Icons.storefront_outlined, size: 18),
-            tooltip: 'Module stores',
-            onPressed: () => ChainStoresDialog.show(context),
+          Padding(
+            padding: const EdgeInsets.only(right: ChainSpace.sm),
+            child: OutlinedButton.icon(
+              icon: const Icon(Icons.add_business_outlined, size: 16),
+              label: Text(l.storesManagerButton),
+              onPressed: () => ChainStoresDialog.show(context),
+              style:
+                  OutlinedButton.styleFrom(visualDensity: VisualDensity.compact),
+            ),
           ),
           IconButton(
             icon: const Icon(Icons.refresh, size: 18),
@@ -1139,38 +1144,49 @@ class _FilterDialogState extends State<_FilterDialog> {
           ],
         ),
       ),
+      // A single Row is the one action child: AlertDialog wraps
+      // `actions` in an OverflowBar (not a Flex), so a bare
+      // `Spacer()` here throws — it needs a Flex parent. Nesting
+      // the buttons in a Row gives the Spacer a valid Flex
+      // ancestor and keeps Reset left / Cancel+Apply right.
       actions: [
-        TextButton(
-          onPressed: () {
-            setState(() {
-              _status = '';
-              _source = '';
-              _installedOnly = false;
-              // Reset puts `installableOnly` back to its default
-              // (on) — the operator hits Reset to escape a
-              // custom-filter state and expects the default view
-              // back, not an everything-including-planned view.
-              _installableOnly = true;
-            });
-          },
-          child: Text(l.storeFilterReset),
-        ),
-        const Spacer(),
-        TextButton(
-          onPressed: () => Navigator.pop(context, null),
-          child: Text(l.buttonCancel),
-        ),
-        FilledButton(
-          onPressed: () => Navigator.pop(
-            context,
-            _FilterOutcome(
-              status: _status,
-              source: _source,
-              installedOnly: _installedOnly,
-              installableOnly: _installableOnly,
+        Row(
+          children: [
+            TextButton(
+              onPressed: () {
+                setState(() {
+                  _status = '';
+                  _source = '';
+                  _installedOnly = false;
+                  // Reset puts `installableOnly` back to its
+                  // default (on) — the operator hits Reset to
+                  // escape a custom-filter state and expects the
+                  // default view back, not an everything-
+                  // including-planned view.
+                  _installableOnly = true;
+                });
+              },
+              child: Text(l.storeFilterReset),
             ),
-          ),
-          child: Text(l.storeFilterApply),
+            const Spacer(),
+            TextButton(
+              onPressed: () => Navigator.pop(context, null),
+              child: Text(l.buttonCancel),
+            ),
+            const SizedBox(width: ChainSpace.sm),
+            FilledButton(
+              onPressed: () => Navigator.pop(
+                context,
+                _FilterOutcome(
+                  status: _status,
+                  source: _source,
+                  installedOnly: _installedOnly,
+                  installableOnly: _installableOnly,
+                ),
+              ),
+              child: Text(l.storeFilterApply),
+            ),
+          ],
         ),
       ],
     );

lib/pages/welcome.dart

@@ -1003,18 +1003,37 @@ class _DocsRow extends StatelessWidget {
                 ],
               );
             }
-            final cardWidth = (constraints.maxWidth - ChainSpace.md) / 2;
-            return Wrap(
-              spacing: ChainSpace.md,
-              runSpacing: ChainSpace.md,
-              children: [
-                for (final d in _kDocs)
-                  SizedBox(
-                    width: cardWidth,
-                    child: _DocCard(entry: d),
+            // Pair the cards into equal-height rows: IntrinsicHeight
+            // + stretch makes the two cards in a row match height
+            // instead of the Wrap's ragged tops (their blurbs differ
+            // in length, especially across locales). An odd trailing
+            // card spans the full width so it reads as intentional
+            // rather than a lonely half-box with dead space beside it.
+            final rows = <Widget>[];
+            for (var i = 0; i < _kDocs.length; i += 2) {
+              if (rows.isNotEmpty) {
+                rows.add(const SizedBox(height: ChainSpace.md));
+              }
+              final left = _kDocs[i];
+              final right = i + 1 < _kDocs.length ? _kDocs[i + 1] : null;
+              if (right == null) {
+                rows.add(_DocCard(entry: left));
+              } else {
+                rows.add(
+                  IntrinsicHeight(
+                    child: Row(
+                      crossAxisAlignment: CrossAxisAlignment.stretch,
+                      children: [
+                        Expanded(child: _DocCard(entry: left)),
+                        const SizedBox(width: ChainSpace.md),
+                        Expanded(child: _DocCard(entry: right)),
+                      ],
+                    ),
                   ),
-              ],
-            );
+                );
+              }
+            }
+            return Column(children: rows);
           },
         ),
       ],