Branding, Excel watermark, live run progress, and uv

- Login and Reports pages: eCare logo, Waystar and Aquilaehr logos (light
  versions for the dark pages), eCare favicon.
- Excel reports: faded eCare/Waystar/Aquila watermark as the sheet
  background on both sheets. Report writer moves to xlsxwriter, the only
  engine that can set a sheet background.
- Reports page: animated run progress (both download lanes piped into the
  Excel sheet) and a plain-language activity feed built from the run log;
  the raw log stays under "Technical log". /status now returns the
  location count.
- Dependencies move from requirements.txt to pyproject.toml + uv.lock;
  Dockerfile installs uv from PyPI and runs uv sync --frozen.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

templates/login.html

@@ -4,6 +4,7 @@
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Sign in · MEK Charge Reconciliation</title>
+<link rel="icon" href="/static/ecare-logo.png">
 <style>
   :root {
     --night: #040b26;
@@ -45,6 +46,14 @@
   .sky .tw { animation: twinkle 4s ease-in-out infinite; animation-delay: var(--d); }
   @keyframes twinkle { 50% { opacity: .15; } }
 
+  .brand {
+    position: absolute;
+    top: 20px;
+    left: 24px;
+    z-index: 1;
+  }
+  .brand img { display: block; width: 72px; height: auto; background: #000; border-radius: 16px; box-shadow: 0 6px 16px rgba(0, 3, 15, .45); }
+
   .stage {
     position: relative;
     min-height: 100%;
@@ -87,6 +96,18 @@
     overflow: visible;
   }
 
+  .sources {
+    display: flex;
+    align-items: center;
+    gap: 20px;
+    margin-top: 28px;
+  }
+  .sources img { display: block; height: auto; }
+  .sources .waystar { width: 132px; }
+  .sources .sep { width: 1px; height: 26px; background: var(--panel-line); }
+  .aquila { display: flex; align-items: center; gap: 8px; font-weight: 600; font-size: 16px; color: #dfe6f7; letter-spacing: .01em; }
+  .aquila img { width: 30px; }
+
   label { display: block; font-weight: 600; margin-bottom: 8px; }
   .field { position: relative; }
   input {
@@ -195,6 +216,8 @@
 
   @media (max-width: 420px) {
     :root { --owl-w: 160px; }
+    .brand { top: 16px; left: 16px; }
+    .brand img { width: 52px; border-radius: 12px; }
   }
   @media (prefers-reduced-motion: reduce) {
     .sky .tw, .owl, .owl * { animation: none !important; transition: none !important; }
@@ -204,6 +227,7 @@
 </head>
 <body>
 <div class="sky" id="sky" aria-hidden="true"></div>
+<header class="brand"><img src="/static/ecare-logo.png" alt="eCare Services" width="206" height="199"></header>
 
 <main class="stage">
   <section class="card">
@@ -272,6 +296,12 @@
     </form>
 
   </section>
+
+  <footer class="sources">
+    <img src="/static/waystar-logo-light.png" alt="Waystar" width="362" height="61" class="waystar">
+    <span class="sep" aria-hidden="true"></span>
+    <span class="aquila"><img src="/static/aquilaehr-logo-light.png" alt="" width="86" height="75">Aquilaehr</span>
+  </footer>
 </main>
 
 <script>
@@ -293,7 +323,7 @@ function drawSky() {
   let seed = 7;
   const rand = () => (seed = (seed * 16807) % 2147483647) / 2147483647;
   const colors = ["#6ea8ff", "#4fd1c5", "#f29c4b", "#dfe7ff"];
-  const keepOut = [...document.querySelectorAll(".card, .owl")].map(e => e.getBoundingClientRect());
+  const keepOut = [...document.querySelectorAll(".card, .owl, .brand, .sources")].map(e => e.getBoundingClientRect());
   let html = "";
   for (let i = 0; i < 60; i++) {
     const tw = rand() < .35, x = rand() * innerWidth, y = rand() * innerHeight;