refactor(claude-code-hooks): extract handlers and session state

Split hook into per-concern modules:
- handlers/ directory for individual hook handlers
- session-hook-state.ts: session-level hook state management

src/hooks/claude-code-hooks/handlers/pre-compact-handler.ts

@@ -0,0 +1,41 @@
+import type { PluginInput } from "@opencode-ai/plugin"
+import { loadClaudeHooksConfig } from "../config"
+import { loadPluginExtendedConfig } from "../config-loader"
+import { executePreCompactHooks, type PreCompactContext } from "../pre-compact"
+import type { PluginConfig } from "../types"
+import { isHookDisabled, log } from "../../../shared"
+
+export function createPreCompactHandler(ctx: PluginInput, config: PluginConfig) {
+	return async (
+		input: { sessionID: string },
+		output: { context: string[] },
+	): Promise<void> => {
+		if (isHookDisabled(config, "PreCompact")) {
+			return
+		}
+
+		const claudeConfig = await loadClaudeHooksConfig()
+		const extendedConfig = await loadPluginExtendedConfig()
+
+		const preCompactCtx: PreCompactContext = {
+			sessionId: input.sessionID,
+			cwd: ctx.directory,
+		}
+
+		const result = await executePreCompactHooks(
+			preCompactCtx,
+			claudeConfig,
+			extendedConfig,
+		)
+
+		if (result.context.length > 0) {
+			log("PreCompact hooks injecting context", {
+				sessionID: input.sessionID,
+				contextCount: result.context.length,
+				hookName: result.hookName,
+				elapsedMs: result.elapsedMs,
+			})
+			output.context.push(...result.context)
+		}
+	}
+}