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>

Dockerfile

@@ -7,8 +7,11 @@ RUN apt-get update \
  && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /app
-COPY requirements.txt .
-RUN pip install --no-cache-dir -r requirements.txt
+# uv from PyPI rather than its ghcr.io image, for the same registry-reset reason as above
+RUN pip install --no-cache-dir uv==0.11.28
+ENV UV_PYTHON_DOWNLOADS=never UV_NO_CACHE=1 PATH="/app/.venv/bin:$PATH"
+COPY pyproject.toml uv.lock ./
+RUN uv sync --frozen
 COPY . .
 
 # headless, system Chromium (Playwright's own browser download is not used)