process_tools 0.31.0

Collection of algorithms and structures to handle processes properly.
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# Feature: Output Capture

### Scope

- **Purpose**: Ensure callers always have full diagnostic context after any subprocess invocation, regardless of exit code.
- **Responsibility**: Owns the `Report` struct that carries command, working directory, stdout, stderr, and error result in one value.
- **In Scope**: `Report` field layout, `Display` formatting for CLI output, manual `Clone` implementation, and population-before-branch ordering inside `run()`.
- **Out of Scope**: How the process is spawned (→ `feature/001`); exit code interpretation semantics (→ `feature/004`).

### Status

- **Version introduced:** 0.1.0
- **Stability:** stable
- **Module path:** `process_tools::process::Report`

### Design

`Report` is unconditionally populated before the exit-code check. In `run()`, `command`, `current_path`, stdout, and stderr are stored into the report struct before the success/failure branch. The divergence happens only at the very end — after all fields are filled. This means `Err(report)` is never a partially-filled struct, so callers can apply identical display or logging logic regardless of branch.

The `Display` impl prefixes the command with `>` and the working directory with `@`, then indents stdout/stderr with two spaces (replacing `\n` with `\n  `). Whitespace-only output blocks are suppressed. This format is designed for inline subprocess tracing in CLI tool output.

`Clone` cannot be derived because `error_tools::Error` is not `Clone`. The manual impl stringifies the error via `.to_string()` to preserve the failure message across the clone boundary, accepting the loss of the original error type.

### Example

```rust
use process_tools::process::Run;

// Both Ok and Err carry a fully populated Report
let result = Run::former()
  .bin_path( "cat" )
  .args( vec![ "/nonexistent".into() ] )
  .current_path( "." )
  .run();

let report = result.unwrap_err();
assert!( !report.command.is_empty() );
assert!( report.error.is_err() );

// Display renders cleanly for CLI output
println!( "{}", report );
// > cat /nonexistent
//   @ .
//   cat: /nonexistent: No such file or directory
```

### Cross-References

| Type | File | Responsibility |
|------|------|----------------|
| source | [src/process.rs](../../src/process.rs) | `Report` struct, `Display` impl, `Clone` impl |
| test | [tests/inc/process_run.rs](../../tests/inc/process_run.rs) | `Report` field population and display tests |
| api | [api/002_report_api.md](../api/002_report_api.md) | Defines fields and method surface of `Report` |
| invariant | [invariant/001_result_contract.md](../invariant/001_result_contract.md) | Guarantees `Report` is always fully populated on both branches |
| feature | [feature/001_process_execution.md](001_process_execution.md) | Execution layer that produces `Report` values |