fix: resolve #3124 #3125 #3127 session tools, cache priming, and compaction loop

- #3124: Session tools now merge SDK and file-backed sessions for SQLite backend
- #3125: Cache priming fixed for OpenCode >=1.3.14 empty workspace
- #3127: Activity-based progress detection prevents infinite compaction on Kimi/Minimax

All 29 new tests pass, 4885 total tests passing.

src/cli/config-manager/bun-install.ts

@@ -1,4 +1,5 @@
 import { existsSync } from "node:fs"
+import { join } from "node:path"
 
 import { getOpenCodeCacheDir } from "../../shared/data-path"
 import { log } from "../../shared/logger"
@@ -40,6 +41,10 @@ export async function runBunInstall(): Promise<boolean> {
   return result.success
 }
 
+function getDefaultWorkspaceDir(): string {
+  return join(getOpenCodeCacheDir(), "packages")
+}
+
 function readProcessOutput(stream: ProcessOutputStream): Promise<string> {
   if (!stream) {
     return Promise.resolve("")
@@ -67,7 +72,7 @@ function logCapturedOutputOnFailure(outputMode: BunInstallOutputMode, output: Bu
 
 export async function runBunInstallWithDetails(options?: RunBunInstallOptions): Promise<BunInstallResult> {
   const outputMode = options?.outputMode ?? "pipe"
-  const cacheDir = options?.workspaceDir ?? getOpenCodeCacheDir()
+  const cacheDir = options?.workspaceDir ?? getDefaultWorkspaceDir()
   const packageJsonPath = `${cacheDir}/package.json`
 
   if (!existsSync(packageJsonPath)) {