## Why
In the `shell_zsh_fork` flow, `codex-shell-escalation` receives the
executable path exactly as the shell passed it to `execve()`. That path
is not guaranteed to be absolute.
For commands such as `./scripts/hello-mbolin.sh`, if the shell was
launched with a different `workdir`, resolving the intercepted `file`
against the server process working directory makes policy checks and
skill matching inspect the wrong executable. This change pushes that fix
a step further by keeping the normalized path typed as `AbsolutePathBuf`
throughout the rest of the escalation pipeline.
That makes the absolute-path invariant explicit, so later code cannot
accidentally treat the resolved executable path as an arbitrary
`PathBuf`.
## What Changed
- record the wrapper process working directory as an `AbsolutePathBuf`
- update the escalation protocol so `workdir` is explicitly absolute
while `file` remains the raw intercepted exec path
- resolve a relative intercepted `file` against the request `workdir` as
soon as the server receives the request
- thread `AbsolutePathBuf` through `EscalationPolicy`,
`CoreShellActionProvider`, and command normalization helpers so the
resolved executable path stays type-checked as absolute
- replace the `path-absolutize` dependency in `codex-shell-escalation`
with `codex-utils-absolute-path`
- add a regression test that covers a relative `file` with a distinct
`workdir`
## Verification
- `cargo test -p codex-shell-escalation`