Add storage stack modules and track them in git

The modules workspace previously ignored every path matching `storage-*`,
which kept all Hypercore, Hyperbee, Hyperdrive, and Autobase packages out
of version control. Narrow .gitignore to test-artifact patterns only so
production category trees are committed.

Storage packages (23 total):
- storage-hypercore (7): replicator, seed-policy, fork-picker, merkle-sync,
  priority-fetch, bitfield-scheduler, audit-chain
- storage-hyperbee (5): batch-write, diff-follow, range-watch,
  secondary-index, tombstone-gc
- storage-hyperdrive (6): entry-catalog, gc-sweep, mirror-sync, mount-bridge,
  version-snapshot, watch-notify
- storage-autobase (5): fork-choice, view-sync, writer-lease, indexer-bus,
  light-writer

Implementation highlights:
- Shared attach/gossip helpers in _shared/storage-gossip-base.js
- P2P modules use Protomux gossip via p2p-bare; local planners omit swarm
- Recent deepen pass: priority queues, batch caps, audit export/import,
  watch/notify aliases on range-watch, fork/view lease helpers, etc.
- Per-package README, docs/api.md, docs/architecture.md, tests, examples

Also update modules/README.md doc hub links for the full storage stack
(hypercore, hyperbee, hyperdrive, autobase).

Co-authored-by: Cursor <[email protected]>

storage-hypercore/hyper-p2p-core-bitfield-scheduler/examples/basic.js

@@ -0,0 +1,13 @@
+require('bare-process/global')
+const { HyperP2PCoreBitfieldScheduler } = require('../index.js')
+
+async function main () {
+  const m = new HyperP2PCoreBitfieldScheduler()
+  m.attach({ length: 0 })
+  m.scheduleRange(0, 8, 1)
+  const r = m.nextRange()
+  console.log('range', r)
+  await m.close()
+  console.log('done')
+}
+main().catch(console.error)