fix: propagate ported exceptions instead of flattening them

`ProcessExecutor::execute_args` existed only to turn `execute`'s
`anyhow::Result` into an exit code of 1, so every one of its ~87 call
sites silently took the "command failed" branch on an error PHP would
have thrown. It is gone; callers use `execute` and propagate with `?`.
Where the enclosing function had no `Result` to propagate into, its
signature grew one, up to and including `Git::get_version`,
`Svn::binary_version`, `GitHub`/`GitLab`/`Bitbucket::authorize_oauth`,
`InitCommand::get_git_config` and `DiagnoseCommand::check_git`.

The VCS drivers had the same problem in the other direction: their
`get_contents` returned `Result<Response, Box<TransportException>>`, a
type too narrow for the PHP method, which lets any Throwable out of the
`catch (TransportException $e)` block. Every non-transport error was
therefore rewritten into a `TransportException` with code 0, which the
callers switch on. They now return
`anyhow::Result<Result<Response, Box<TransportException>>>`: the outer
`Result` carries what PHP does not catch, the inner one the exception
the drivers handle.

That signature also restores `GitLabDriver::getContents`: the 400/401
`TransportException`s it raises to force authentication are thrown
inside its own `try` block and handled by its own `catch`, but the port
returned them straight to the caller, so the authentication flow behind
them never ran.

`impl_php_exception!` gains `From<Box<$ty>> for anyhow::Error` so a
caught exception can be re-propagated with `?`.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/crates/shirabe/src/package/locker.rs b/crates/shirabe/src/package/locker.rs
index 36edd29f..d6db1ab7 100644
--- a/crates/shirabe/src/package/locker.rs
+++ b/crates/shirabe/src/package/locker.rs
@@ -798,14 +798,14 @@ impl Locker {
                 .unwrap_or_default();
             match source_type.as_deref().unwrap_or("") {
                 "git" => {
-                    GitUtil::clean_env(&self.process);
+                    GitUtil::clean_env(&self.process)?;
 
                     let no_show_signature_flags =
-                        GitUtil::get_no_show_signature_flags(&self.process);
+                        GitUtil::get_no_show_signature_flags(&self.process)?;
                     let mut args: Vec<String> =
                         vec!["-n1".to_string(), "--format=%ct".to_string(), source_ref];
                     args.extend(no_show_signature_flags);
-                    let command = GitUtil::build_rev_list_command(&self.process, args);
+                    let command = GitUtil::build_rev_list_command(&self.process, args)?;
                     let mut output = PhpMixed::Null;
                     if 0 == self.process.borrow_mut().execute(
                         command,
@@ -816,7 +816,7 @@ impl Locker {
                             &GitUtil::parse_rev_list_output(
                                 output.as_string().unwrap_or(""),
                                 &self.process,
-                            ),
+                            )?,
                             None,
                         );
                         if preg_is_match(php_regex!(r"{^\s*\d+\s*$}"), &output_str) {