## Summary
`cargo test` has entails both running standard Rust tests and doctests.
It turns out that the doctest discovery is fairly slow, and it's a cost
you pay even for crates that don't include any doctests.
This PR disables doctests with `doctest = false` for crates that lack
any doctests.
For the collection of crates below, this speeds up test execution by
>4x.
E.g., before this PR:
```
Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml
Time (mean ± σ): 1.849 s ± 4.455 s [User: 0.752 s, System: 1.367 s]
Range (min … max): 0.418 s … 14.529 s 10 runs
```
And after:
```
Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml
Time (mean ± σ): 428.6 ms ± 6.9 ms [User: 187.7 ms, System: 219.7 ms]
Range (min … max): 418.0 ms … 436.8 ms 10 runs
```
For a single crate, with >2x speedup, before:
```
Benchmark 1: cargo test -p codex-utils-string
Time (mean ± σ): 491.1 ms ± 9.0 ms [User: 229.8 ms, System: 234.9 ms]
Range (min … max): 480.9 ms … 512.0 ms 10 runs
```
And after:
```
Benchmark 1: cargo test -p codex-utils-string
Time (mean ± σ): 213.9 ms ± 4.3 ms [User: 112.8 ms, System: 84.0 ms]
Range (min … max): 206.8 ms … 221.0 ms 13 runs
```
Co-authored-by: Codex <noreply@openai.com>
## Summary
Persisted subagent parent/child topology currently leaks through
`StateRuntime`'s SQLite-specific thread-spawn helpers. This PR
introduces a narrow `AgentGraphStore` boundary so follow-up work can
route graph operations through a local or remote store without coupling
orchestration code directly to the state DB graph API.
## Changes
- Adds the new `codex-agent-graph-store` crate.
- Defines a flat `AgentGraphStore` trait for the v1 graph surface:
upsert edge, set edge status, list direct children, and list
descendants.
- Adds public graph types for `ThreadSpawnEdgeStatus`,
`AgentGraphStoreError`, and `AgentGraphStoreResult`.
- Implements `LocalAgentGraphStore` on top of an existing
`codex_state::StateRuntime`, preserving today's SQLite-backed
`thread_spawn_edges` behavior.
- Registers the crate in Cargo/Bazel metadata.
This PR only adds the local contract and implementation; call-site
migration and the remote gRPC store are left to the follow-up PRs in the
stack.
## Testing
- `cargo test -p codex-agent-graph-store`
The new unit tests cover local parity with the existing `StateRuntime`
graph methods, `Open`/`Closed` filtering, status updates, and stable
breadth-first descendant ordering.