refactor(opencode-skill-loader): split loader and merger into focused modules

Extract skill loading pipeline into single-responsibility modules:
- skill-discovery.ts, skill-directory-loader.ts, skill-deduplication.ts
- loaded-skill-from-path.ts, loaded-skill-template-extractor.ts
- skill-template-resolver.ts, skill-definition-record.ts
- git-master-template-injection.ts, allowed-tools-parser.ts
- skill-mcp-config.ts, skill-resolution-options.ts
- merger/ directory for skill merging logic

src/features/opencode-skill-loader/skill-resolution-options.ts

@@ -0,0 +1,7 @@
+import type { BrowserAutomationProvider, GitMasterConfig } from "../../config/schema"
+
+export interface SkillResolutionOptions {
+	gitMasterConfig?: GitMasterConfig
+	browserProvider?: BrowserAutomationProvider
+	disabledSkills?: Set<string>
+}