feat(ui): layout polish — fill dead space, pair/box/collapse, warning weight, dialog glass

Implements the layout-improvement suggestions from the layout audit (visual arrangement
only; no functionality added or removed):

- Send/Receive: the recent-activity list now grows to fill the space below the fixed
  compose/receive card (more history visible), with a centered empty-state when there is
  none — instead of leaving dead canvas.
- Shield/Merge: pair the Fee and UTXO-Limit fields on one row to tighten vertical rhythm.
- Market: extend + frame the portfolio group-list as one contained panel (with a bottom
  edge) and center its empty-state, closing the previously un-anchored gap.
- Overlay dialogs: raise the card glass fill/border alpha (35/50 -> 60/90 of 255) so the
  dialog card reads as a distinct surface over busy backdrops (global, all overlays).
- Wallets: size the list height to the actual wallet count instead of always reserving 7
  rows, removing the large gap before the scan/create prompts (still scrolls when many).
- Contacts: width-aware address truncation shows more of the address on wide rows.
- Transfer Funds: give the "sends the full balance" warning a warning icon + color so the
  stakes stand out from the neutral result-preview lines.
- First-run wizard: collapse a completed Step 1 (Appearance) to the compact pill like
  Step 2, so a finished step is no longer taller than the active one.
- Explorer: distribute the Chain card's two stats to match the density of the sibling
  metrics grid.
- Validate Address: a "Results will appear here" caption fills the pre-interaction blank.
- Change Passphrase: add the warning banner its sibling security dialogs have.
- Migration ShowSeed: box the 24-word mnemonic grid (a GlassSectionScope behind the
  existing RenderSeedWordGrid) so the critical secret reads as a distinct artifact —
  purely visual, no seed/logic/state change.

Verified at 1280 across full-node + Lite + Windows (ctest green) and an adversarial diff
review (clean). New i18n key backfilled into all 8 languages.

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

src/ui/windows/contacts_tab.cpp

@@ -207,6 +207,28 @@ static bool isShieldedAddr(const std::string& a) {
     return !a.empty() && a[0] == 'z';
 }
 
+// Width-aware middle-ellipsis truncation (mirrors the add/edit dialog's local fitMiddle lambda, but
+// file-scope so the Cards/List rows can share it too): keeps head + tail, shrinking symmetrically
+// until the rendered width fits maxW. minFront/minBack are the schema-configured floor — below that
+// the fixed-length util::truncateMiddle result is used instead, so very cramped rows still read as
+// "front...back" rather than collapsing to a near-empty stub. Addresses are ASCII, so byte-wise
+// trimming is safe.
+static std::string truncateAddressToWidth(const std::string& s, ImFont* f, float size, float maxW,
+                                          int minFront, int minBack) {
+    const std::string floor = util::truncateMiddle(s, minFront, minBack);
+    auto w = [&](const std::string& t){ return f->CalcTextSizeA(size, FLT_MAX, 0, t.c_str()).x; };
+    if (w(s) <= maxW) return s;                 // fits in full — no truncation needed at all
+    if (maxW <= 0.0f) return floor;              // no room to measure against — fall back to the floor
+    const std::string ell = "\xE2\x80\xA6";
+    size_t head = s.size() / 2, tail = s.size() - head;
+    while (head + tail > static_cast<size_t>(minFront + minBack)) {
+        std::string cand = s.substr(0, head) + ell + s.substr(s.size() - tail);
+        if (w(cand) <= maxW) return cand;
+        if (head >= tail) --head; else --tail;
+    }
+    return floor;   // couldn't fit even at the configured floor — use the fixed-length result
+}
+
 // Accent colour for a contact's address type (Z = shielded/green, T = transparent/amber), tuned per
 // theme. File-scope so both the list rows and the edit-dialog preview share one source of truth.
 static ImU32 contactTypeColor(bool shielded, bool light) {
@@ -1219,10 +1241,13 @@ void RenderContactsTab(App* app)
                 dl->AddText(lblF, lblSz, ImVec2(tx, ty), material::OnSurface(), entry.label.c_str());
                 dl->PopClipRect();
                 // Un-collapse to the full address on hover (clipped to the text column so it never
-                // runs under the trailing actions); middle-truncated otherwise.
+                // runs under the trailing actions); otherwise middle-truncated to FIT the actual text
+                // column width (tx..textMaxX) rather than a fixed char count — wide rows show more of
+                // the address instead of leaving a dead gap before the action-icon cluster.
                 std::string addr = rowHovered
                     ? entry.address
-                    : util::truncateMiddle(entry.address, addrFrontLbl.truncate, addrBackLbl.truncate);
+                    : truncateAddressToWidth(entry.address, adrF, adrSz, textMaxX - tx,
+                                             addrFrontLbl.truncate, addrBackLbl.truncate);
                 dl->PushClipRect(ImVec2(tx, mn.y), ImVec2(textMaxX, mx.y), true);
                 dl->AddText(adrF, adrSz, ImVec2(tx, ty + lblSz + 3.0f * dp),
                             material::OnSurfaceMedium(), addr.c_str());