Restructure chat service, web routes, and add test suite

Split monolithic chat service into modular structure with Matrix client
support, extract web server into per-resource route modules, introduce
bootstrap/main-loop separation, and add comprehensive vitest coverage
across services, repositories, and utilities. Adds project docs and
CLAUDE.md agent instructions.

src/services/strategy-selector.ts

@@ -16,11 +16,13 @@ export class StrategySelector {
   constructor(
     private config: Config,
     private messagesRepo: MessagesRepository,
-    private logger: Logger
+    private logger: Logger,
+    section: 'strategies' | 'chatStrategies' = 'strategies',
   ) {
-    this.variants = config.strategies.variants;
-    this.explorationRate = config.strategies.explorationRate;
-    this.minSamples = config.strategies.minSamples;
+    const cfg = config[section];
+    this.variants = cfg.variants;
+    this.explorationRate = cfg.explorationRate;
+    this.minSamples = cfg.minSamples;
   }
 
   selectStrategy(): SelectedStrategy | null {