feat(theseus/toolbar): drag-handles + pin right-side items on URL/search resize

Two fixes bundled:

1) Right-side items (download, extension dock, Theseus button) no longer
   slide leftward when the URL bar is capped. Added margin-right: auto
   to .urlwrap under every capped state (data-urlsize=medium/compact
   and the new data-urlwidth override) so the leftover flex space sits
   AFTER the URL bar, keeping the right group pinned to the right edge.
   Verified: logo's gap from bar's right edge stays at 10px across
   default / urlBarSize=compact / urlBarWidthPx=500 / reset.

2) Drag handles for live resize. A 6-px col-resize strip sits on the
   trailing edge of .urlwrap and the leading edge of .searchbox; a
   pointerdown/move/up dance updates the width live via a CSS custom
   property and persists to settings on release. Two new keys:
   - urlBarWidthPx (0-1800, 0 = follow size preset)
   - searchBoxWidthPx (0-800, 0 = follow size preset)
   When either is non-zero, the corresponding CSS override wins over
   the discrete size preset. Preload gets setSetting so the drag can
   push the persistent value from chrome.

Visual affordance: handles are transparent by default, gain a faint
acid tint on hover and while dragging.

chrome.html

@@ -147,13 +147,28 @@
   /* address bar. flex:1 by default consumes remaining space; user can cap
      it via Settings > Appearance > Address bar size so the extension dock
      gets more room. min-width guards against squeezing the URL invisible. */
-  .urlwrap { flex: 1 1 auto; min-width: 200px; display: flex; align-items: center; gap: 4px; background: var(--surface); border: 1px solid var(--line);
+  .urlwrap { position: relative; flex: 1 1 auto; min-width: 200px; display: flex; align-items: center; gap: 4px; background: var(--surface); border: 1px solid var(--line);
              border-radius: 999px; padding: 0 6px 0 4px; }
-  .bar[data-urlsize="medium"]  .urlwrap { flex: 0 1 640px; }
+  /* Capped URL bar: pin the trailing items (download / extensions / logo /
-  .bar[data-urlsize="compact"] .urlwrap { flex: 0 1 400px; }
+     Theseus) to the RIGHT edge instead of packing them next to the URL bar
+     — a smaller address bar shouldn't slide everything leftward. margin-
+     right: auto on the URL bar consumes the slack. */
+  .bar[data-urlsize="medium"]  .urlwrap { flex: 0 1 640px; margin-right: auto; }
+  .bar[data-urlsize="compact"] .urlwrap { flex: 0 1 400px; margin-right: auto; }
+  .bar[data-urlwidth]          .urlwrap { flex: 0 0 var(--urlbar-w, auto); margin-right: auto; }
+  .searchbox { position: relative; }
   .bar[data-searchsize="hidden"]  .searchbox { display: none; }
   .bar[data-searchsize="compact"] .searchbox { width: 180px; }
   .bar[data-searchsize="wide"]    .searchbox { width: 400px; }
+  .bar[data-searchwidth]          .searchbox { width: var(--searchbox-w, 300px); }
+  /* Drag-to-resize handles: a thin invisible strip on the trailing edge of
+     .urlwrap and the leading edge of .searchbox. col-resize cursor makes
+     the affordance visible; a faint acid tint on hover confirms it's live. */
+  .urldrag, .searchdrag { position: absolute; top: 0; bottom: 0; width: 6px; cursor: col-resize; z-index: 10; background: transparent; }
+  .urldrag    { right: -3px; }
+  .searchdrag { left:  -3px; }
+  .urldrag:hover, .searchdrag:hover,
+  .urldrag.dragging, .searchdrag.dragging { background: rgba(214,255,61,.35); }
   /* Adaptive toolbar. A ResizeObserver on .bar sets data-responsive:
        "0" wide  — everything visible (default)
        "1" tight — auto-hide the search box, min-width for URL bar drops
@@ -339,8 +354,10 @@
       <span class="reg" id="reg" hidden></span>
       <button class="pwchip" id="pwchip" title="Fill password for this site" hidden><span id="pwchipCount"></span><svg viewBox="0 0 16 16" aria-hidden="true"><circle cx="6" cy="9" r="3.2" fill="none" stroke="currentColor" stroke-width="1.5"/><path d="M8.8 8.6 L14 8.6 M13.2 8.6 L13.2 11 M11.5 8.6 L11.5 10.4" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round"/></svg></button>
       <button class="star" id="star" title="Save this page">☆</button>
+      <div class="urldrag" id="urldrag" title="Drag to resize"></div>
     </div>
     <div class="searchbox">
+      <div class="searchdrag" id="searchdrag" title="Drag to resize"></div>
       <button id="engineBtn" class="engine-btn" title="Choose search engine"><span id="engineIcon"></span><span class="cv">▾</span></button>
       <input id="search" placeholder="Search" spellcheck="false">
     </div>
@@ -1197,15 +1214,66 @@
   syncHeight();
   // Toolbar sizing: URL bar + search box widths follow user preference.
   // Applied as data-attrs on .bar so CSS handles the layout swap.
+  // urlBarWidthPx / searchBoxWidthPx (integers > 0) come from the drag
+  // handles; when present they OVERRIDE the discrete size preset. Set to
+  // null (or 0) to restore preset behavior.
   function applyBarSizes(s) {
     if (!s) return;
     const bar = $("bar");
     if (s.urlBarSize)    bar.dataset.urlsize    = s.urlBarSize;
     if (s.searchBoxSize) bar.dataset.searchsize = s.searchBoxSize;
+    const uw = Number(s.urlBarWidthPx) || 0;
+    if (uw > 0) { bar.dataset.urlwidth = "1"; bar.style.setProperty("--urlbar-w", uw + "px"); }
+    else        { delete bar.dataset.urlwidth; bar.style.removeProperty("--urlbar-w"); }
+    const sw = Number(s.searchBoxWidthPx) || 0;
+    if (sw > 0) { bar.dataset.searchwidth = "1"; bar.style.setProperty("--searchbox-w", sw + "px"); }
+    else        { delete bar.dataset.searchwidth; bar.style.removeProperty("--searchbox-w"); }
     syncHeight();
   }
   T.getSettings && T.getSettings().then(applyBarSizes);
   T.onSettingsUpdate && T.onSettingsUpdate(applyBarSizes);
+
+  // Drag handles: right edge of .urlwrap resizes the URL bar; left edge of
+  // .searchbox resizes the search box. Persists to settings.urlBarWidthPx /
+  // searchBoxWidthPx on release, which then wins over the size preset.
+  function makeDragHandle(handleEl, targetEl, opts) {
+    let startX = 0, startW = 0, dragging = false, lastW = 0;
+    handleEl.addEventListener("pointerdown", (e) => {
+      if (e.button !== 0) return;
+      dragging = true;
+      startX = e.clientX;
+      startW = targetEl.getBoundingClientRect().width;
+      handleEl.setPointerCapture(e.pointerId);
+      handleEl.classList.add("dragging");
+      e.preventDefault();
+    });
+    handleEl.addEventListener("pointermove", (e) => {
+      if (!dragging) return;
+      const dx = e.clientX - startX;
+      // Left-edge handles (search) grow when dragged LEFT (dx < 0).
+      const w = Math.round(Math.max(opts.min, Math.min(opts.max, startW + (opts.reverseX ? -dx : dx))));
+      lastW = w;
+      opts.applyLive(w);
+    });
+    const stop = (e) => {
+      if (!dragging) return;
+      dragging = false;
+      handleEl.classList.remove("dragging");
+      try { handleEl.releasePointerCapture(e.pointerId); } catch {}
+      if (lastW > 0 && T.setSetting) T.setSetting(opts.settingKey, lastW);
+    };
+    handleEl.addEventListener("pointerup", stop);
+    handleEl.addEventListener("pointercancel", stop);
+  }
+  const barEl2 = $("bar");
+  makeDragHandle($("urldrag"), $("bar").querySelector(".urlwrap"), {
+    min: 200, max: 1800, settingKey: "urlBarWidthPx", reverseX: false,
+    applyLive: (w) => { barEl2.dataset.urlwidth = "1"; barEl2.style.setProperty("--urlbar-w", w + "px"); },
+  });
+  makeDragHandle($("searchdrag"), $("bar").querySelector(".searchbox"), {
+    min: 120, max: 800, settingKey: "searchBoxWidthPx", reverseX: true,
+    applyLive: (w) => { barEl2.dataset.searchwidth = "1"; barEl2.style.setProperty("--searchbox-w", w + "px"); },
+  });
   // Self-heal: some menu-close paths (drag interruptions, focus flips) can
   // leave the chrome view taller than the natural body-scrollHeight. Every
   // 750 ms with no menu open, re-sync — main.js only re-layouts when the

main.js

@@ -230,6 +230,10 @@ const SETTINGS_DEFAULTS = {
   // room to grow. The search box is fixed-width; hidden removes it.
   urlBarSize:     "wide",     // compact | medium | wide (default)
   searchBoxSize:  "normal",   // hidden | compact | normal (default) | wide
+  // Drag-set widths in pixels. Non-zero → override the corresponding size
+  // preset; zero/null → follow the preset. Set by the toolbar drag handles.
+  urlBarWidthPx:      0,
+  searchBoxWidthPx:   0,
 };
 // Applying the theme via nativeTheme.themeSource makes prefers-color-scheme update
 // in every renderer (chrome, settings, popover, page views) with no per-view IPC.

preload.js

@@ -26,6 +26,7 @@ contextBridge.exposeInMainWorld("theseus", {
   toggleTor: () => ipcRenderer.invoke("toggle-tor"),
   openSettings: () => ipcRenderer.invoke("open-settings"),
   getSettings: () => ipcRenderer.invoke("settings-get"),
+  setSetting: (key, val) => ipcRenderer.invoke("settings-set", key, val),
   onSettingsUpdate: (cb) => ipcRenderer.on("settings-update", (_e, d) => cb(d)),
   toggleSiteInfo: (rect) => ipcRenderer.invoke("toggle-site-info", rect),
   switchToBcnr: () => ipcRenderer.invoke("switch-to-bcnr"),