fix: single uv install for unified dep resolution (root cause of click/typer crash)

Dockerfile

@@ -15,10 +15,20 @@ RUN pip install uv
 # Copy requirements first for Docker layer caching
 COPY requirements-ci-english.txt requirements-ci-hindi.txt ./
 
-# Install ALL Python deps as root (before switching user)
-RUN uv pip install --system --no-cache fastapi uvicorn pydantic "click>=8.2.0"
-RUN uv pip install --system --no-cache -r requirements-ci-english.txt
-RUN uv pip install --system --no-cache -r requirements-ci-hindi.txt
+# ROOT CAUSE FIX: Install ALL dependencies in a SINGLE command
+# so uv can resolve the full dependency graph at once.
+#
+# Previously, 3 separate `uv pip install` commands each resolved
+# independently. The kokoro→misaki→spacy→typer→click chain needs
+# click>=8.2.0 for Choice[T] generics, but a later install step
+# was downgrading click, causing TypeError at import time.
+#
+# In GitHub Actions CI this works because everything is installed
+# in one `uv pip install -r requirements.txt` call.
+RUN uv pip install --system --no-cache \
+    fastapi uvicorn pydantic \
+    -r requirements-ci-english.txt \
+    -r requirements-ci-hindi.txt
 
 # Now create non-root user (HF Spaces requirement)
 RUN useradd -m -u 1000 user