feat: wire BuildPulse to Appwrite-backed persistence

docs/ARCHITECTURE.md

@@ -2,7 +2,7 @@
 
 ## Architecture Goal
 
-Keep v0.1 boring, local-first, and easy to understand.
+Keep v0.1 boring, Appwrite-backed, and easy to understand.
 BuildPulse should be simple enough for AI coding agents to modify safely without losing context.
 
 ## Recommended v0.1 Stack
@@ -11,19 +11,11 @@ Preferred simple stack:
 - React
 - Vite
 - TypeScript if practical
-- LocalStorage or IndexedDB
+- Tiny local API bridge to Appwrite on the Unraid server
+- Appwrite document persistence for canonical state
+- LocalStorage cache fallback in the browser
 - Markdown/JSON export
 
-Optional if file-backed storage is explicitly wanted:
-- Tiny Node/Express backend
-- Files:
-  - `data/project.json`
-  - `data/features/*.json`
-  - `data/parking_lot/*.json`
-  - `data/pulses.jsonl`
-
-Do not add a database in v0.1.
-
 ## Design Principle
 
 BuildPulse is pulse-compatible, not pulse-dependent.
@@ -139,17 +131,21 @@ src/
 
 ## Storage Strategy
 
-### Fastest v0.1
+### v0.1 Canonical Persistence
 
-Use browser storage.
+Use Appwrite on the Unraid server as the source of truth.
 - Store one serialized app state object.
 - Include a schema version.
+- Mirror the latest good state into browser storage as a cache/fallback.
 - Support export/import to avoid lock-in.
 
-Example key:
+Current runtime shape:
 
 ```text
-buildpulse.appState.v1
+Appwrite project: freecastle
+Database: freecastle
+Collection: runtime
+Document: buildpulse_state
 ```
 
 ### Future File-Backed Mode
@@ -160,12 +156,16 @@ Later, the same data can be saved as:
 data/
   project.json
   features/
-  parking_lot/
+    feature_001.json
+    feature_002.json
+  parking_lot.json
   pulses.jsonl
 ```
 
 Do not build this unless explicitly requested for v0.1.
 
+For v0.1, do not build this file-backed mode unless explicitly requested. Export/import should still preserve this same logical structure.
+
 ## Migration Strategy
 
 Every stored state must include:
@@ -189,7 +189,6 @@ v0.1 Pulse events should already include:
 - `agent_id`
 - `pulse_type`
 - `message`
-- `structured_payload`
 - `confidence_score`
 - `evidence_refs`
 - `trace_id`
@@ -201,7 +200,6 @@ Even if many fields are optional or manually filled.
 Do not introduce:
 - Redux unless needed
 - Complex state machines
-- Backend services
 - Event buses
 - WebSockets
 - Plugins