feat: ingestion status dashboard (weave docs status)

[maximilien]

Problem

During 4-8 hour image ingestion runs, there is no way to see what is happening.
Client0 wrote a separate polling script that runs doc-count queries and parses log files
to show progress.

Proposed Solution

New command `weave docs status`:

```bash
weave docs status --milvus-local
```

Output:
```
📊 Collection Status (milvus-local)
════════════════════════════════════
Collection Docs Status Last Updated
AuctionListings 267 ✅ ok 2026-02-17 14:32
AuctionListings_OSS 267 ✅ ok 2026-02-17 14:45
AuctionImages 6591 ✅ ok 2026-02-17 19:22
AuctionImages_OSS 1423 🔄 ... 2026-02-17 21:45 (in progress)

⚙️ Active ingestion: AuctionImages_OSS
File: 2023-catalogue.pdf [7/9 files]
Chunks: 1,234 created
Elapsed: 2h 14m
```

Live mode (`--watch`): refresh every 5 seconds.

Priority

P2 — v0.9.30 target (~5 hours)

[maximilien]

Target: v0.9.29 (week of Feb 24, Thu-Fri)

Implementation plan:

• Thu Feb 27: Core — list collections + doc counts + active ingestion detection from checkpoint
• Fri Feb 28: Polish — --watch mode + --json + tests + release v0.9.29

Dependency: Issue #38 must ship first (checkpoint file format needed for active ingestion detection)

[maximilien]

Stale check: no activity in 7+ days. Is this still planned for Phase 2 or should we defer/close? Please update with current status or plan.