docs(8.0): Phase F — deep clean across 21 docs

Aligned every public doc to the 8.0 contract: filesystem + memory adapters
only, vector index provider terminology (config.vector with recall +
quantization + persistMode knobs), no cloud storage adapters, no closed-
source product names.

Tier 1 — heavier rewrites:
- docs/architecture/storage-architecture.md
- docs/architecture/data-storage-architecture.md
- docs/architecture/distributed-storage.md DELETED — content was 100%
  cloud-coordination examples with no 8.0 substance.
- docs/guides/distributed-system.md DELETED — same reason; no inbound refs.
- docs/SCALING.md rewritten for single-node guidance.
- docs/PLUGINS.md, docs/augmentations/{COMPLETE-REFERENCE,README}.md:
  HnswProvider→VectorIndexProvider, hnsw→vector key.
- docs/PERFORMANCE.md, docs/BATCHING.md cloud-detection + sharding
  sections replaced with single-node vector tuning + filesystem framing.

Tier 2 — surgical renames + cloud-section deletions:
- architecture/{index,initialization-and-rebuild,overview}.md
- transactions.md, DEVELOPER_LEARNING_PATH.md
- vfs/{VFS_API_GUIDE,COMMON_PATTERNS}.md
- api/README.md, guides/{inspection,import-flow}.md

Tier 3 — light edits:
- docs/README.md, architecture/augmentation-system-audit.md

MIGRATION-V3-TO-V4.md untouched (internal migration doc, no stale terms).

docs/transactions.md

@@ -11,7 +11,7 @@ Brainy's transaction system provides **atomic operations** with automatic rollba
 - **Atomicity**: All operations succeed or all rollback
 - **Consistency**: Indexes and storage remain consistent
 - **Automatic**: Transparently used by all `brain.add()`, `brain.update()`, `brain.delete()`, and `brain.relate()` operations
-- **Compatible**: Works seamlessly with COW, sharding, type-aware storage, and distributed storage
+- **Compatible**: Works seamlessly with COW, sharding, and type-aware storage
 
 ## Architecture
 
@@ -154,37 +154,27 @@ await brain.update({
 - Storage layer uses O(1) ID-first path construction
 - No type cache needed (removed in a previous version)
 - Type counters adjusted on commit/rollback
-- 40x faster on cloud storage (eliminates 42-type search)
+- 40x faster path lookups (eliminates 42-type search)
 
-### Distributed Storage
+### Storage Adapter Interface
 
 ✅ **Fully Compatible**
 
-Transactions work with distributed/remote storage:
+Transactions go through the `StorageAdapter` interface, so both shipped adapters (filesystem, memory) and any custom plugin adapter inherit the same atomicity guarantees:
 
 ```typescript
-// Works with S3, Azure, GCS, etc.
 const brain = new Brainy({
- storage: {
- type: 's3Compatible',
- config: { /* S3 config */ }
- }
+  storage: { type: 'filesystem', rootDirectory: './data' }
 })
 
-// Transactions ensure atomicity at write coordinator level
-await brain.add({ data: { name: 'Remote Entity' }, type: NounType.Thing })
+await brain.add({ data: { name: 'Entity' }, type: NounType.Thing })
 ```
 
 **How It Works:**
 - Transactions operate through `StorageAdapter` interface
-- Remote storage adapters implement same interface
-- Atomicity guaranteed at write-coordinator level
-- Read-after-write consistency maintained
-
-**Design Philosophy:**
-- **Single-node writes** (most common): Fully atomic ✅
-- **Distributed reads + centralized writes**: Transactions on primary ✅
-- **Multi-primary**: Transactions per-instance, cross-instance via coordinator ✅
+- Custom adapters registered via the plugin system implement the same interface
+- Atomicity guaranteed at the write-coordinator level
+- Read-after-write consistency maintained inside a single Brainy process
 
 ## Examples
 
@@ -404,17 +394,17 @@ setInterval(() => {
 ### 5. Understand Atomicity Guarantees
 
 **What Transactions GUARANTEE:**
-- ✅ Atomicity within single Brainy instance
+- ✅ Atomicity within a single Brainy process
 - ✅ Consistent state across all indexes
 - ✅ Automatic rollback on failure
-- ✅ Works with all storage adapters (local, remote, COW, sharded)
+- ✅ Works with all storage adapters (filesystem, memory, custom plugin adapters)
 
 **What Transactions DON'T Provide:**
 - ❌ Two-phase commit across multiple Brainy instances
-- ❌ Distributed locking across nodes
+- ❌ Distributed locking across processes
 - ❌ Cross-datacenter ACID guarantees
 
-**Design:** Transactions ensure atomicity at the **write coordinator level**. For multi-instance scenarios, use `DistributedCoordinator`.
+**Design:** Transactions ensure atomicity at the **write-coordinator level** inside one process. Cross-instance coordination, if you need it, lives in your service layer.
 
 ## Testing Transactions
 
@@ -453,7 +443,6 @@ See `tests/transaction/integration/` for comprehensive integration tests coverin
 - COW integration (`cow-transactions.test.ts`)
 - Sharding integration (`sharding-transactions.test.ts`)
 - TypeAware integration (`typeaware-transactions.test.ts`)
-- Distributed storage integration (`distributed-transactions.test.ts`)
 
 ## Troubleshooting
 
@@ -552,7 +541,7 @@ interface StorageAdapter {
 }
 ```
 
-**Key Insight:** All storage adapters (filesystem, S3, Azure, GCS, memory) implement this interface. Transactions work with **any** storage adapter automatically.
+**Key Insight:** Both shipped storage adapters (filesystem, memory) — and any custom plugin adapter — implement this interface. Transactions work with **any** storage adapter automatically.
 
 ## Additional Resources
 
@@ -565,13 +554,13 @@ interface StorageAdapter {
 
 - Initial transaction system release
  - Atomic operations with rollback
- - Compatible with COW, sharding, type-aware, distributed
+ - Compatible with COW, sharding, type-aware storage
  - 36/36 unit tests passing
  - 35 integration test scenarios
 
 ## Summary
 
-Brainy's transaction system provides **production-ready atomic operations** with automatic rollback. It works transparently with all Brainy APIs and is fully compatible with advanced features like COW, sharding, type-aware storage, and distributed storage.
+Brainy's transaction system provides **production-ready atomic operations** with automatic rollback. It works transparently with all Brainy APIs and is fully compatible with advanced features like COW, sharding, and type-aware storage.
 
 **Key Takeaways:**
 - ✅ **Automatic**: No manual transaction management needed