INTEROP-8979: Add per-rule Slack notifications on issue creation

[amp-rh]

Summary

• Add optional slack_channel field to firewatch config rules (both failure_rules and success_rules). When set, firewatch sends a Slack notification after creating a new Jira issue, updating a duplicate, or filing a success story.
• Supports !default to read from $FIREWATCH_DEFAULT_SLACK_CHANNEL, matching the pattern used by all other rule fields.
• Notifications can be delivered via Slack bot token (--slack-bot-token) or incoming webhook URL (--slack-webhook-url).
• Empty or absent slack_channel on a rule skips notification entirely; no behavioral change for existing configs.

Config example

{
  "failure_rules": [
    {
      "step": "install",
      "failure_type": "pod_failure",
      "classification": "Infrastructure",
      "jira_project": "LPINTEROP",
      "slack_channel": "#ocp-ci-firewatch-tool"
    }
  ]
}

Files changed

File	Change
src/objects/rule.py	Add _get_slack_channel with !default / env var support
src/objects/slack_base.py	Add post_webhook static method for webhook-based posting
src/objects/configuration.py	Accept slack_bot_token and slack_webhook_url params
src/report/report.py	Send Slack after issue creation, duplicate comment, success story
src/commands/report.py	Add --slack-bot-token and --slack-webhook-url CLI options

Related

• INTEROP-8979: https://issues.redhat.com/browse/INTEROP-8979
• INTEROP-8976 (token rotation alerts): https://issues.redhat.com/browse/INTEROP-8976 / PR INTEROP-8979: Add per-rule Slack notifications #274

Test plan

• All 222 unit tests pass (including 5 new tests for slack_channel rule parsing)
• Review _notify_slack in Report for correct webhook vs bot-token fallback
• Verify Slack message format with a real webhook URL
• Test with config that has no slack_channel (existing behavior unchanged)
• Test with slack_channel: "!default" and FIREWATCH_DEFAULT_SLACK_CHANNEL env var

Made with Cursor

[openshift-ci]

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[amp-rh]

Superseded by #274, which includes this feature plus token expiry alerts (INTEROP-8976) and doc fixes from the staging walkthrough.