feat(mavweb): /ecosystem page consuming Nexus/Praxis/Hexis + shell fixes

Add a read-only /ecosystem page that consumes the sibling services'
JSON APIs (Nexus entities, Praxis attention, Hexis capabilities),
fetched concurrently with honest per-panel error states. Siblings stay
headless — mavweb is their human surface (arch §16). Wired via mavweb
-nexus/-praxis/-hexis flags; mavweb joins the ecosystem compose network.

Fix mobile horizontal overflow across all pages: .content is a flex
child with default min-width:auto, so it refused to shrink below the
tables' intrinsic width. min-width:0 lets wide tables pan inside .scroll
instead of dragging the page sideways. Verified via CDP geometry check
(scrollWidth === clientWidth at 430px).

Also includes in-progress Ethos UI redesign, ecosystem deploy compose,
and planning docs.

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

cmd/mavweb/static/mavweb.js

@@ -47,15 +47,15 @@
   let paletteEl = null;
   let paletteInput = null;
 
-  // Page entries for the command palette
+  // Page entries for the command palette — uses ethos-icons.svg sprite
   const palettePages = [
-    { label: 'Dashboard', url: '/dash', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect x="3" y="3" width="7" height="7" rx="1"/><rect x="14" y="3" width="7" height="7" rx="1"/><rect x="14" y="14" width="7" height="7" rx="1"/><rect x="3" y="14" width="7" height="7" rx="1"/></svg>' },
-    { label: 'History', url: '/history', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="10"/><polyline points="12 6 12 12 16 14"/></svg>' },
-    { label: 'Rule Trace', url: '/trace', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="22 12 18 12 15 21 9 3 6 12 2 12"/></svg>' },
-    { label: 'Notifications', url: '/notifications', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M6 8a6 6 0 0 1 12 0c0 7 3 9 3 9H3s3-2 3-9"/><path d="M10.3 21a1.94 1.94 0 0 0 3.4 0"/></svg>' },
-    { label: 'Voice', url: '/', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M12 1a3 3 0 0 0-3 3v8a3 3 0 0 0 6 0V4a3 3 0 0 0-3-3z"/><path d="M19 10v2a7 7 0 0 1-14 0v-2"/><line x1="12" y1="19" x2="12" y2="23"/><line x1="8" y1="23" x2="16" y2="23"/></svg>' },
-    { label: 'Tools', url: '/tools', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M14.7 6.3a1 1 0 0 0 0 1.4l1.6 1.6a1 1 0 0 0 1.4 0l3.77-3.77a6 6 0 0 1-7.94 7.94l-6.91 6.91a2.12 2.12 0 0 1-3-3l6.91-6.91a6 6 0 0 1 7.94-7.94l-3.76 3.76z"/></svg>' },
-    { label: 'Passkey', url: '/auth/passkey', icon: '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect x="3" y="11" width="18" height="11" rx="2" ry="2"/><path d="M7 11V7a5 5 0 0 1 10 0v4"/></svg>' },
+    { label: 'Dashboard', url: '/dash', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-grid"/></svg>' },
+    { label: 'History', url: '/history', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-clock"/></svg>' },
+    { label: 'Rule Trace', url: '/trace', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-wave"/></svg>' },
+    { label: 'Notifications', url: '/notifications', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-bell"/></svg>' },
+    { label: 'Voice', url: '/', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-mic"/></svg>' },
+    { label: 'Tools', url: '/tools', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-settings"/></svg>' },
+    { label: 'Passkey', url: '/auth/passkey', icon: '<svg width="14" height="14"><use href="/ethos-icons.svg#i-lock"/></svg>' },
   ];
 
   function buildPalette() {
@@ -65,7 +65,7 @@
     paletteEl.innerHTML =
       '<div class=cmd-palette>' +
       '<div class=cmd-palette-input>' +
-      '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="11" cy="11" r="8"/><line x1="21" y1="21" x2="16.65" y2="16.65"/></svg>' +
+      '<svg width="14" height="14"><use href="/ethos-icons.svg#i-search"/></svg>' +
       '<input type=text placeholder="Go to page or run action…" spellcheck=false autofocus>' +
       '</div>' +
       '<div class=cmd-palette-list id=paletteList></div>' +