## Summary
- match the exec-process structure to filesystem PR #15232
- expose `ExecProcess` on `Environment`
- make `LocalProcess` the real implementation and `RemoteProcess` a thin
network proxy over `ExecServerClient`
- make `ProcessHandler` a thin RPC adapter delegating to `LocalProcess`
- add a shared local/remote process test
## Validation
- `just fmt`
- `CARGO_TARGET_DIR=~/.cache/cargo-target/codex cargo test -p
codex-exec-server`
- `just fix -p codex-exec-server`
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Co-authored-by: Codex <noreply@openai.com>
Stacked PR 2/3, based on the stub PR.
Adds the exec RPC implementation and process/event flow in exec-server
only.
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Co-authored-by: Codex <noreply@openai.com>
Stacked PR 1/3.
This is the initialize-only exec-server stub slice: binary/client
scaffolding and protocol docs, without exec/filesystem implementation.
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Co-authored-by: Codex <noreply@openai.com>
