feat(cli): add resolve/reopen/mute issue actions

[kevinsheth]

Why

rollbaz supported read-only triage but could not apply common incident actions. This adds write flows so users can resolve, reopen, or mute directly from the CLI.

What changed

• added write commands:
  • rollbaz resolve <counter>
  • rollbaz reopen <counter>
  • rollbaz mute <counter> [--for <duration>]
• added confirmation guard for write operations with --yes override
• added Rollbar item patch support (PATCH /api/1/item/{id}) with typed payload fields
• added app-layer action methods that update then fetch the latest item snapshot
• added action output payloads (action + updated issue) for human/json modes
• updated README to:
  • document write commands
  • clarify that write commands require a write-capable project token
  • remove verbose output implementation details

Validation

• go test ./...
• go test -race ./...
• go test ./internal/... -coverprofile=coverage.out && go run ./scripts/coveragecheck -min 85 -file coverage.out
• go run golang.org/x/vuln/cmd/govulncheck@v1.1.4 ./...
• go run github.com/golangci/golangci-lint/cmd/golangci-lint@v1.64.8 run