Agent jobs (spawn_agents_on_csv) + progress UI (#10935)

## Summary
- Add agent job support: spawn a batch of sub-agents from CSV, auto-run,
auto-export, and store results in SQLite.
- Simplify workflow: remove run/resume/get-status/export tools; spawn is
deterministic and completes in one call.
- Improve exec UX: stable, single-line progress bar with ETA; suppress
sub-agent chatter in exec.

## Why
Enables map-reduce style workflows over arbitrarily large repos using
the existing Codex orchestrator. This addresses review feedback about
overly complex job controls and non-deterministic monitoring.

## Demo (progress bar)
```
./codex-rs/target/debug/codex exec \
  --enable collab \
  --enable sqlite \
  --full-auto \
  --progress-cursor \
  -c agents.max_threads=16 \
  -C /Users/daveaitel/code/codex \
  - <<'PROMPT'
Create /tmp/agent_job_progress_demo.csv with columns: path,area and 30 rows:
path = item-01..item-30, area = test.

Then call spawn_agents_on_csv with:
- csv_path: /tmp/agent_job_progress_demo.csv
- instruction: "Run `python - <<'PY'` to sleep a random 0.3–1.2s, then output JSON with keys: path, score (int). Set score = 1."
- output_csv_path: /tmp/agent_job_progress_demo_out.csv
PROMPT
```

## Review feedback addressed
- Auto-start jobs on spawn; removed run/resume/status/export tools.
- Auto-export on success.
- More descriptive tool spec + clearer prompts.
- Avoid deadlocks on spawn failure; pending/running handled safely.
- Progress bar no longer scrolls; stable single-line redraw.

## Tests
- `cd codex-rs && cargo test -p codex-exec`
- `cd codex-rs && cargo build -p codex-cli`

codex-rs/core/tests/suite/sqlite_state.rs

@@ -33,7 +33,7 @@ async fn new_thread_is_recorded_in_state_db() -> Result<()> {
 
     let thread_id = test.session_configured.session_id;
     let rollout_path = test.codex.rollout_path().expect("rollout path");
-    let db_path = codex_state::state_db_path(test.config.codex_home.as_path());
+    let db_path = codex_state::state_db_path(test.config.sqlite_home.as_path());
 
     for _ in 0..100 {
         if tokio::fs::try_exists(&db_path).await.unwrap_or(false) {
@@ -161,7 +161,7 @@ async fn backfill_scans_existing_rollouts() -> Result<()> {
 
     let test = builder.build(&server).await?;
 
-    let db_path = codex_state::state_db_path(test.config.codex_home.as_path());
+    let db_path = codex_state::state_db_path(test.config.sqlite_home.as_path());
     let rollout_path = test.config.codex_home.join(&rollout_rel_path);
     let default_provider = test.config.model_provider_id.clone();
 
@@ -220,7 +220,7 @@ async fn user_messages_persist_in_state_db() -> Result<()> {
     });
     let test = builder.build(&server).await?;
 
-    let db_path = codex_state::state_db_path(test.config.codex_home.as_path());
+    let db_path = codex_state::state_db_path(test.config.sqlite_home.as_path());
     for _ in 0..100 {
         if tokio::fs::try_exists(&db_path).await.unwrap_or(false) {
             break;