Docker rewrite and optimizations (#321)

* Optimizations of dockerfile

Massive test optimizations with drop in image size to about 256mb from about 1.2 gb. Drawback is that I currently have to keep the dockerfile playwright version matched to the package.json version

* further optimizations

Removed redundant (hopefully) sessions directory creation during build

* Fix docker cron dependencies

Small fix that should make cron run properly

* Major docker update!

- **Dockerfile rewritten as a multi-stage build**
  - Split into a “builder” stage (`node:18-slim`) to install dependencies and compile TypeScript, and a “runtime” stage (official Playwright image) to run the script.
  - This keeps build tools and dependencies out of the final image, making it smaller, faster to pull, and more secure.

- **Entrypoint script (`entrypoint.sh`)**
  - Introduced an entrypoint that runs inside the container at startup to:
    1. Set the container’s timezone (`TZ`) correctly, based on the environment or defaulting to UTC.
    2. Validate that the user provided a `CRON_SCHEDULE` (exiting early with an error if missing).
    3. Optionally perform an initial run of the script immediately (when `RUN_ON_START=true`), without any random sleep.
  - Centralizing setup in an entrypoint keeps the Dockerfile simpler and ensures proper signal handling.

- **`run_daily.sh` improvements**
  - Removed custom browser-path override so Playwright uses bundled browsers in the official image.
  - Added a lock using `flock` to prevent overlapping runs if a previous run is still in progress.
  - Retained the random sleep between 5 and 50 minutes before each run.
  - Logs are timestamped and clearly report success or failure.

- **Cron template tweaks**
  - Updated `src/crontab.template` so that each job line redirects both stdout and stderr into Docker’s stdout (`>> /proc/1/fd/1 2>&1`), making it easy to view logs via `docker logs`.

- **Initial-run logic**
  - The entrypoint checks `RUN_ON_START=true` and, if set, invokes `npm start` immediately (without random sleep). This provides an immediate first execution on container startup.
  - Scheduled runs via cron still go through the normal `run_daily.sh` (with sleep and locking).

- **Cron logging and visibility**
  - By redirecting cron job output to the container’s stdout, all logs (initial run and scheduled runs) appear in `docker logs`, avoiding the need to tail log files manually.

- **Error handling and validation**
  - Entry point exits early if `CRON_SCHEDULE` is missing, preventing silent misconfiguration.
  - If the initial run fails, it logs a warning but still starts cron so future scheduled runs can proceed.
  - `run_daily.sh` will exit early if a previous run is still active (locking), avoiding overlapping executions.

* Docker (multi-stage) improvements

- added cron logging in entrypoint and fixed timezone support for cron-invoked script runs
- further optimized multi-stage dockerfile
- bumped playwright version to 1.52.0 in dockerfile and package.json
- added customization and enable/disable randomization for cron start times
- optionally add container health  monitor and resource limits in compose.yaml

package.json

@@ -43,8 +43,8 @@
     "http-proxy-agent": "^7.0.2",
     "https-proxy-agent": "^7.0.6",
     "ms": "^2.1.3",
-    "playwright": "1.47.2",
-    "rebrowser-playwright": "1.47.2",
+    "playwright": "1.52.0",
+    "rebrowser-playwright": "1.52.0",
     "socks-proxy-agent": "^8.0.5",
     "ts-node": "^10.9.2"
   }