v0.27.3:0 - cap image resolution (fix oversized-image 400); remove vision-check button

A 12MP photo expands past vLLM's ~4096-image-token limit -> 400. Cap via
--mm-processor-kwargs max_pixels in the qwen36 recipe so big images auto-
downscale server-side for every /v1 consumer (verified live: 400->200).
Remove the v0.27.2 in-dashboard vision-check button per owner request; the
vision badge already signals capability.

image/app/static/index.html

@@ -365,20 +365,6 @@
         </form>
       </dialog>
 
-      <dialog id="vision-dialog" class="modal">
-        <form method="dialog" class="modal-form" id="vision-form">
-          <h3>Vision check<span id="vc-model" class="muted small"></span></h3>
-          <p class="muted small">Send an image to the running model and see what it reads back — handy for confirming OCR on a real photo (e.g. a business card). Sent over the same <code>/v1</code> endpoint your apps use; nothing leaves the LAN.</p>
-          <label class="modal-row"><span>Image</span><input type="file" id="vc-file" accept="image/*"></label>
-          <img id="vc-preview" class="vc-preview hidden" alt="selected image preview">
-          <label class="modal-row"><span>Prompt</span><textarea id="vc-prompt" rows="3">This is a business card. Extract every field as JSON with keys: name, title, company, phone, email, website, address. Output only the JSON.</textarea></label>
-          <div class="vc-result hidden" id="vc-result"></div>
-          <div class="modal-actions">
-            <button type="button" id="vc-run" class="btn primary">Run</button>
-            <button class="btn" value="cancel">Close</button>
-          </div>
-        </form>
-      </dialog>
 
       <section id="download-panel" class="download-panel hidden">
         <div class="download-form" id="download-form">