feat: initial implementation of uptodownbot

Telegram bot for downloading media from any site using yt-dlp.
Supports audio/video/both, quality selection, language picker,
container format selection, playlist pagination, progress updates,
per-user quotas, user preferences, download history, cancel at any step,
polling and webhook modes, proxy support, and SQLite persistence.

Dockerfile

@@ -0,0 +1,24 @@
+FROM golang:1.26.4-alpine3.23 AS builder
+
+WORKDIR /src
+
+ARG HTTP_PROXY
+ARG HTTPS_PROXY
+ENV HTTP_PROXY=${HTTP_PROXY}
+ENV HTTPS_PROXY=${HTTPS_PROXY}
+
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . .
+RUN go build -o /usr/local/bin/uptodown-bot ./cmd/bot/
+
+FROM alpine:3.23
+
+RUN apk add --no-cache ffmpeg yt-dlp ca-certificates tzdata
+
+WORKDIR /data
+
+COPY --from=builder /usr/local/bin/uptodown-bot /usr/local/bin/uptodown-bot
+VOLUME ["/data"]
+
+CMD ["uptodown-bot"]