Add settings tooltips and search to the web UI

Help users quickly find settings and understand how each one works.

Tooltips: a new delegated controller (static/v3/js/tooltips.js) drives an
accessible (i) info tooltip that appears on hover, keyboard focus, and tap.
A shared `help_tip` Jinja macro (partials/_macros.html) emits the trigger;
the plugin config macro and the core settings partials now surface help
text through it. Per the design, the always-visible field help paragraphs
are folded into the tooltip to declutter the forms, and the hardware/display
settings carry authored detail (default, range, recommendation).

Search: a global header search box finds settings across every settings tab
— even ones not yet opened — via a lazy client-side index built by scanning
the same field markup (static/v3/js/settings-search.js). Selecting a result
switches tabs, waits for the field to load, then scrolls to and flashes it.
A per-tab filter box hides non-matching fields on the current tab.

Plugin settings get tooltips for free by reusing each field's schema
`description`; every settings field also gets a stable `setting-<tab>-<key>`
anchor id for search navigation.

Styling uses the existing --color-* theme vars so light/dark mode both work,
and honors prefers-reduced-motion. Adds Flask render smoke tests that assert
each settings partial ships tooltips, anchors, and a filter box.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014gZxznuxw8L92FUMBN3Nqz

web_interface/templates/v3/base.html

@@ -882,6 +882,25 @@
 
                 <!-- Connection status and theme toggle -->
                 <div class="flex items-center space-x-4">
+                    <!-- Global settings search -->
+                    <div class="relative hidden sm:block" id="settings-search-wrap">
+                        <input id="settings-search"
+                               type="text"
+                               role="combobox"
+                               aria-expanded="false"
+                               aria-autocomplete="list"
+                               aria-controls="settings-search-results"
+                               aria-label="Search settings"
+                               placeholder="Search settings…"
+                               autocomplete="off"
+                               class="form-control text-sm pl-8 pr-4 py-1.5 w-48 lg:w-64">
+                        <i class="fas fa-search absolute left-3 top-1/2 transform -translate-y-1/2 text-gray-400 text-xs" aria-hidden="true"></i>
+                        <div id="settings-search-results"
+                             role="listbox"
+                             aria-label="Settings search results"
+                             class="hidden absolute right-0 mt-1 w-80 max-h-96 overflow-y-auto"></div>
+                    </div>
+
                     <!-- Theme toggle -->
                     <button id="theme-toggle"
                             type="button"
@@ -4747,7 +4766,11 @@
 
     <!-- Custom v3 JavaScript -->
     <script src="{{ url_for('static', filename='v3/app.js') }}" defer></script>
-    
+
+    <!-- Settings tooltips + settings search -->
+    <script src="{{ url_for('static', filename='v3/js/tooltips.js') }}" defer></script>
+    <script src="{{ url_for('static', filename='v3/js/settings-search.js') }}" defer></script>
+
     <!-- Modular Plugin Management JavaScript -->
     <!-- Load utilities first -->
     <script src="{{ url_for('static', filename='v3/js/utils/error_handler.js') }}" defer></script>