fix(agent): recall search + memory_dir fallback + bersihkan dead llm_client

Hasil audit round 4 (workflow/hive_mind + memory + semantic_search).

- fix(memory): recall.search selama ini TIDAK pernah dipakai — tool
  mengiklankan keyword search di skema tapi run() cuma list semua nama.
  Kini search benar-benar memfilter (cocok di name/description/content,
  case-insensitive), + output 'No memories match' bila kosong.
- fix(memory): ToolCtxBuilder tidak punya setter memory_dir dan tak ada
  call-site yang mengisinya — remember/recall/forget memakai PathBuf kosong
  dan menulis memory ke CWD (bukan lokasi persisten). Tambah setter
  memory_dir + worktrees_dir, dan helper resolve_memory_dir() yang fallback
  ke Store::new().memory_dir bila ctx.memory_dir kosong; dipakai di ketiga
  tool memory.
- refactor(workflow): hapus LlmClient dummy di WorkflowRun (dibuat dengan
  API key kosong + model default + base_url default lalu tak pernah dipakai
  — execute_workflow menerimanya sebagai _llm_client). Kini execute_workflow
  tak ambil parameter tak terpakai; LLM asli tetap lewat execute_primitive
  yang resolve kredensial dengan benar.
- test: +2 (recall search memfilter; resolve_memory_dir fallback/eksplisit).

Catatan audit yang dilaporkan (belum difix): synth_consensus hanya
menggabungkan output (label Consensus menyesatkan, bukan sintesis LLM), dan
semantic_search memegang Mutex index global saat full rebuild (bottleneck
saat paralel) + index tidak workspace-aware.

PENTING (infra): disk root 100% saat kerja. Saya bebaskan ~4.6G dari /tmp +
cache aman (sekai*, verify-z, bun/npm cache). target/debug di repo = 38G —
rampah, perlu cargo clean + rebuild (jangan dibiarkan).

Cargo.lock

@@ -4862,7 +4862,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-api"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "argon2",
@@ -4885,7 +4885,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-application"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "base64",
@@ -4903,7 +4903,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-bootstrap"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "chrono",
@@ -4920,7 +4920,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-daemon"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "base64",
@@ -4944,7 +4944,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-domain"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "base64",
@@ -4960,7 +4960,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-gateway"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "axum",
@@ -4987,7 +4987,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-grpc"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "axum",
@@ -5004,7 +5004,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-infrastructure"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "argon2",
@@ -5052,7 +5052,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-tui"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "base64",
@@ -5078,7 +5078,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-web"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "axum",
@@ -5098,7 +5098,7 @@ dependencies = [
 
 [[package]]
 name = "zesdex-ws"
-version = "1.19.6"
+version = "1.20.0"
 dependencies = [
  "anyhow",
  "axum",