(v2.2.0) Add outage update emails, recipient diffs, Docker, and confi…

…g reload

On each cron tick the config file is reloaded so recipient/bill/SMTP edits
apply without restart. Same-day outage time changes send an update invite
to all current recipients; newly added recipients get invites only for
already-known outages. Emails now include a clear text body explaining
what the message is and how to add the calendar invite.

Also adds a Dockerfile (make docker) and fixes cache file writes to
truncate before rewriting so shortened JSON cannot leave stale bytes.

Change installation method of goreleaser

Change goreleaser version in release.yml

Change goreleaser version to 1

Fix install.sh not exist in gh releases

(v2.0.0) Add support socks5 proxy for mailing

Breaking Changes:

auth_token field now moved outside of the clients section.

Previous release was like this:
```toml

log_level = -8
cron_job = "@daily"
wait_time = 120

[clients.my_client]
smtp_name = "gmail"
bill_id = ""
bill_ids = ["", ""]
recipients = [""]
```

Now it's like this:
```toml
log_level = -8
cron_job = "@daily"
wait_time = 120
auth_token = ""

[clients.my_client]
smtp_name = "gmail"
bill_id = ""
bill_ids = ["", ""]
recipients = [""]
```

auth_token in client object will be ignore.

New Features:

SMTP connections can now be routed through a SOCKS5 proxy. Configure it as an optional sub-table under any SMTP entry:

```toml
[smtp.gmail.proxy]
host = "127.0.0.1"
port = "1080"
username = ""   # leave empty if proxy needs no auth
password = ""
```

Omitting the `[smtp.<name>.proxy]` section (or leaving `host` empty) keeps the existing direct-connection behaviour unchanged.

Also, A multi-platform `install.sh` is now shipped with every release. It auto-detects OS (`linux` / `darwin` / `windows`) and architecture (`amd64` / `arm64`), downloads the correct binary, and installs it to `/usr/local/bin`:
curl -fsSL https://github.com/dozheiny/barghman/releases/latest/download/install.sh | bash

No Go compiler required.

Bug fixes:

Spurious `ERROR client quit error failed` log on successful Gmail sends**
Gmail's SMTP server responds with `250 2.0.0 OK` to `QUIT`, which the Go `net/smtp` client surfaces as a non-nil error after the data writer is closed.
This was previously logged unconditionally at `ERROR` level, making every successful send look like a failure.
It is now handled correctly: the error is checked and, if present, logged at `WARN` level only.

**Full Changelog:** v1.0.0...v2.0.0

v1.0.0

This is the v1.0.0 release of Barghman. Several changes are included:
- Barghman now runs as a systemd template, allowing it to be used as a systemd service.
- A man page has been added, explaining configuration, installation, and usage.
- Added wait_time configuration for controlling the delay for each client.
- Added bill_ids configuration to support multiple bill IDs.
- Added delete cache functionality.
- README format has been converted to Markdown.
- AUR package is now available.
- Build process now uses GoReleaser instead of GitHub Actions.

There are two breaking changes in this release:
To support multiple email origins, each SMTP configuration must now be mapped to its respective client. This is a breaking change, as you must specify the mapping between SMTP configurations and clients.
The use_cron flag has been removed. Cron jobs are now triggered automatically when the cron_job value is not empty.
This release also fixes email delivery issues and corrects several typos.

v1.0.0-rc.2

This is the second beta release of Barghman. Several changes are included:
- Barghman now runs as a systemd template, allowing it to be used as a systemd service.
- A man page has been added, explaining configuration, installation, and usage.
- Added wait_time configuration for controlling the delay for each client.
- Added bill_ids configuration to support multiple bill IDs.
- Added delete cache functionality.
- README format has been converted to Markdown.
- AUR package is now available.
- Build process now uses GoReleaser instead of GitHub Actions.

There are two breaking changes in this release:
To support multiple email origins, each SMTP configuration must now be mapped to its respective client. This is a breaking change, as you must specify the mapping between SMTP configurations and clients.
The use_cron flag has been removed. Cron jobs are now triggered automatically when the cron_job value is not empty.
This release also fixes email delivery issues and corrects several typos.

This is the first beta release of Barghman. Several changes are inclu…

…ded:

Barghman now includes a systemd template, allowing it to be used as a systemd service, If you run `make install` it will be added to systemd.

A man page has been added, explaining configuration, installation, and usage.

Added wait_time configuration for controlling the delay for each client.

Added bill_ids configuration to support multiple bill IDs.

README format has been converted to Markdown.

There are two breaking changes in this release:
1. To support multiple email origins, each SMTP configuration must now be mapped to its respective client. This is a breaking change, as you must specify the mapping between SMTP configurations and clients.
2. The use_cron flag has been removed. Cron jobs are now triggered automatically when the cron_job value is not empty.
This release also fixes email delivery issues and corrects several typos.

This release also fixes email delivery issues and corrects several typos.