[Feature] gitt issues list can filter by repo but not by lifecycle state — add a `--status` filter (registered/active/completed/cancelled)

[taillred]

Summary

gitt issues list supports filtering by repository via --repo (#892, shipped in #910), but there is no way to filter by issue lifecycle state. Add a client-side --status filter:

​bash gitt issues list --status active gitt issues list --status registered gitt issues list --status completed gitt issues list --status cancelled ​

Supported values should match the four statuses the CLI already renders in the Status column: Registered, Active, Completed, Cancelled.

Motivation

The most common read-side workflow is finding actionable issues — in practice, Active bounties. Issues are never removed from contract storage, so completed and cancelled entries accumulate permanently and the signal-to-noise of an unfiltered listing only degrades as the subnet grows.

Today the workarounds are the same shell gymnastics #892 described for repos:

​```bash

eyeball the colored Status column across every row

$ gitt issues list

rebuild the filter in jq, losing the table rendering

$ gitt issues list --json | jq '.issues[] | select(.status == "Active")'
​```

Proposed behavior

• --status as a case-insensitive click.Choice over the four statuses, matching the existing --network option style.
• Applies identically to the table output and --json output.
• Composes with --repo; --id takes precedence (same semantics the --repo filter already has).
• No flag provided → behavior unchanged.

A client-side filter applied after the contract read is sufficient — the same approach as the existing --repo filter in issues_list (gittensor/cli/issue_commands/view.py).