Add PDF search feature to pdf-server (#445)

* Add PDF search feature to pdf-server

Adds full-text search functionality to the PDF viewer:

- Search button in toolbar (Ctrl/Cmd+F to open)
- Search bar with input, prev/next navigation, match count
- Text extraction and caching across all pages
- Highlight overlays using DOM Range API
- Case-insensitive search across entire document
- Keyboard shortcuts: Ctrl+F (open), Enter (next), Shift+Enter (prev), Escape (close)

Changes:
- mcp-app.html: Add search button, search bar, highlight layer
- src/mcp-app.css: Add search/highlight styles and PDF.js text layer rules
- src/mcp-app.ts: Add search state, functions, event listeners

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* update screenshots

* Add fullscreen button to threejs-server

* Fix prettier formatting

* Move search bar below toolbar, right-aligned

* Make search bar compact and right-aligned

* Float search bar over page content

* Ctrl/Cmd+F toggles search; pass through to browser when empty

* Hide search nav controls until query is entered

* Skip scroll when search highlight is already visible

* Fix search bar right-edge alignment with container border

* Prevent browser find when our search is open with text

* Cmd+F when search input is focused passes through to browser find

* Fix prettier formatting in README

* Remove unrelated formatting and threejs changes from PR

* prettier

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

examples/pdf-server/mcp-app.html

@@ -11,7 +11,11 @@
       <div id="loading" class="loading">
         <div class="spinner"></div>
         <p id="loading-text">Loading PDF...</p>
-        <div id="progress-container" class="progress-container" style="display: none">
+        <div
+          id="progress-container"
+          class="progress-container"
+          style="display: none"
+        >
           <div id="progress-bar" class="progress-bar"></div>
         </div>
         <p id="progress-text" class="progress-text"></p>
@@ -57,16 +61,58 @@
             <button id="zoom-in-btn" class="zoom-btn" title="Zoom in (+)">
               +
             </button>
-            <button id="fullscreen-btn" class="fullscreen-btn" title="Toggle fullscreen">
+            <button
+              id="search-btn"
+              class="search-btn"
+              title="Search (Ctrl+F)"
+            ></button>
+            <button
+              id="fullscreen-btn"
+              class="fullscreen-btn"
+              title="Toggle fullscreen"
+            >
               ⛶
             </button>
           </div>
         </div>
+        <!-- Search bar below toolbar, right-aligned -->
+        <div id="search-bar" class="search-bar" style="display: none">
+          <input
+            id="search-input"
+            class="search-input"
+            type="text"
+            placeholder="Search..."
+            autocomplete="off"
+          />
+          <span id="search-match-count" class="search-match-count"></span>
+          <button
+            id="search-prev-btn"
+            class="search-nav-btn"
+            title="Previous (Shift+Enter)"
+          >
+            &#x25B2;
+          </button>
+          <button
+            id="search-next-btn"
+            class="search-nav-btn"
+            title="Next (Enter)"
+          >
+            &#x25BC;
+          </button>
+          <button
+            id="search-close-btn"
+            class="search-nav-btn"
+            title="Close (Esc)"
+          >
+            &#x2715;
+          </button>
+        </div>
 
         <!-- Single Page Canvas Container -->
         <div class="canvas-container">
           <div class="page-wrapper">
             <canvas id="pdf-canvas"></canvas>
+            <div id="highlight-layer" class="highlight-layer"></div>
             <div id="text-layer" class="text-layer"></div>
           </div>
         </div>