Feat/jobs tag filter

[Divyansh Maheshwari (divyansh1010x)]

Summary

Adds the ability to filter the Jobs list by one or more tag key/value pairs (e.g. owner:#dev-core, dag_id:sales_etl) directly from the Jobs filter panel.

The backend already supports the ?tags=key:value,key:value query param (exact match per tag, AND semantics across tags), so this PR is frontend-only, it adds the UI and wires it into the existing filter flow.

Testing

1. Seed jobs with known tags

Paste this whole block into a terminal. It creates 4 jobs with distinct, predictable tags (auth header is X-Heimdall-User):

API=http://127.0.0.1:9090/api/v1
seed() {  # seed <name> <tag> [tag...]
  local name=$1; shift; local t=""
  for x in "$@"; do t="${t:+$t,}\"$x\""; done
  curl -s -X POST "$API/job" -H "X-Heimdall-User: tester" -H 'Content-Type: application/json' \
    -d "{\"name\":\"$name\",\"version\":\"1.0.0\",\"context\":{},\"tags\":[$t],\"command_criteria\":[\"type:ping\"],\"cluster_criteria\":[\"type:localhost\"]}" \
    >/dev/null && echo "  created $name -> $*"
}

echo "Seeding..."
seed tagdemo-a owner:#dev-core env:prod    task_id:extract
seed tagdemo-b owner:#dev-core env:staging task_id:extract
seed tagdemo-c owner:#data-eng env:prod    task_id:load
seed tagdemo-d owner:#data-eng env:prod    task_id:extract
echo "Done."

2. Verify in the UI

Enter key and value in separate fields and verify its working.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.