refactor: reorganize project structure and fix broken references

- Move scripts to scripts/ directory (roda.sh, prepara_db.py, etc.)
- Move shell config to shell/ directory (Caddyfile, auth.py, haloy.yml)
- Move basedosdados.duckdb to data/ directory
- Update Dockerfile and start.sh with new file paths
- Update README.md with correct script paths
- Remove Python ask.py (replaced by Rust binary in ask/ask)
- Add Rust source files (schema_filter.rs, sql_generator.rs, table_selector.rs)
- Remove sentence-transformer dependencies from ask
- Move docs and context artifacts to their directories

scripts/build_ask.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+set -e
+
+cd "$(dirname "$0")"
+
+echo "=== Building ask binary for Linux x86_64 ==="
+echo "Using Debian x86_64 container for native build..."
+
+# Build in an x86_64 Debian container - this gives us a real x86_64 environment
+# so we can build natively without cross-compilation complexity
+# Use ask/ as context to avoid .dockerignore excluding src/
+docker build \
+    --platform linux/amd64 \
+    -t ask-builder \
+    --build-arg BUILDKIT_INLINE_CACHE=1 \
+    -f - ask/ <<'EOF'
+FROM rust:1.85-slim
+
+RUN apt-get update -qq && \
+    apt-get install -y --no-install-recommends \
+        build-essential pkg-config libssl-dev && \
+    apt-get clean && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /build
+
+COPY . ./
+RUN cargo build --release --locked
+
+FROM scratch
+COPY --from=0 /build/target/release/ask /ask
+EOF
+
+echo "=== Extracting binary ==="
+# Extract the binary from the container
+docker run --rm --platform linux/amd64 ask-builder cat /ask > ./ask/target/release/ask
+
+# Make it executable
+chmod +x ./ask/target/release/ask
+
+echo "=== Binary built successfully ==="
+file ./ask/target/release/ask
+ls -lh ./ask/target/release/ask