ui: V09 redesign - Control/Program/Console/Settings shell

Replaces the legacy side-menu chrome with a 4-tab top header.

- index.pug: tablet/kiosk fit-to-viewport script, header tab nav,
  estop/state badges in header.
- app.js: route hash to (control|program|console|<settings-family>),
  multi-section settings shell.
- control-view: header DRO, jog grid, MDI/probe/macros panels.
- program-view + program-mixin: file browser + toolpath preview +
  run/pause/stop, replaces the legacy 'macros' tab content.
- console-view: MDI shell, message log, indicators.
- settings-shell-view: rail-driven inner pages (Display & Units,
  Probing, G-code & Motion, Macros, Network, etc.).
- settings-view: filter Svelte SettingsView to one rail section.
- SettingsView.svelte: tag every section with data-sec=… so the
  filter above can hide non-matching ones.
- style.styl: ~2700 lines of V09 layout, DRO, jog grid, status
  strip, and tablet/kiosk variants.

No A-axis / auxiliary-axis content lives on this branch.

src/pug/templates/console-view.pug

@@ -0,0 +1,67 @@
+script#console-view-template(type="text/x-template")
+  .console-page
+    .console-card
+      .ptab-bar
+        button.ptab(:class="{active: sub === 'mdi'}", @click="select_sub('mdi')")
+          .fa.fa-keyboard
+          |  MDI
+        button.ptab(:class="{active: sub === 'messages'}", @click="select_sub('messages')")
+          .fa.fa-comment-dots
+          |  Messages
+          span.ptab-badge(v-if="unread_messages") {{unread_messages}}
+        button.ptab(:class="{active: sub === 'indicators'}", @click="select_sub('indicators')")
+          .fa.fa-bell
+          |  Indicators
+
+      // ----- MDI -----
+      .mdi-pane(v-show="sub === 'mdi'")
+        .mdi-input
+          span.prompt G>
+          input(type="text", v-model="mdi", :disabled="!can_mdi",
+            @keyup.enter="submit_mdi", placeholder="enter a G-code command…")
+          button.mdi-send(:disabled="!can_mdi || !mdi", @click="submit_mdi")
+            .fa.fa-paper-plane
+            |  SEND
+        .mdi-keys
+          button.mkey(@click="prepend('G0 ')") G0
+          button.mkey(@click="prepend('G1 ')") G1
+          button.mkey(@click="prepend('G2 ')") G2
+          button.mkey(@click="prepend('G3 ')") G3
+          button.mkey(@click="prepend('G28 ')") G28
+          button.mkey(@click="prepend('G92 ')") G92
+          button.mkey(@click="prepend('M3 ')") M3
+          button.mkey(@click="prepend('M5 ')") M5
+          button.mkey(@click="append('X')") X
+          button.mkey(@click="append('Y')") Y
+          button.mkey(@click="append('Z')") Z
+          button.mkey(@click="append('W')") W
+          button.mkey(@click="append('F')") F
+          button.mkey(@click="append('S')") S
+          button.mkey.clear(@click="mdi = ''") CLEAR
+          button.mkey.send(:disabled="!can_mdi || !mdi", @click="submit_mdi") SEND ↵
+
+        em Machine units: #[strong {{mach_units}}]. G20/G21 to switch.
+
+        .mdi-history(:class="{placeholder: !history.length}")
+          span.mdi-empty(v-if="!history.length") MDI history will display here.
+          .h-row(v-for="item in history", @click="load_history($index)",
+            track-by="$index")
+            span.h-cmd {{item}}
+            span.h-status ↻
+
+      // ----- Messages -----
+      .messages-pane(v-show="sub === 'messages'")
+        .msg-empty(v-if="!$root.messages_log.length")
+          .fa.fa-circle-check
+          |  No messages.
+        .msg(v-for="m in $root.messages_log",
+          :class="m.level === 'warning' ? 'warn' : 'info'", track-by="$index")
+          .mi
+            .fa(:class="m.level === 'warning' ? 'fa-triangle-exclamation' : 'fa-circle-info'")
+          div
+            .mtitle {{m.text}}
+            .mtime ID {{m.id}}
+
+      // ----- Indicators -----
+      .indicators-pane(v-show="sub === 'indicators'")
+        indicators(:state="state", :template="template")