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>

4 files changed, 12 insertions, 10 deletions

diff --git a/crates/shirabe/tests/command/init_command_test.rs b/crates/shirabe/tests/command/init_command_test.rs
index e82f2bd7..ffb98fbb 100644
--- a/crates/shirabe/tests/command/init_command_test.rs
+++ b/crates/shirabe/tests/command/init_command_test.rs
@@ -617,7 +617,7 @@ fn test_get_git_config() {
     let _restore_home = RestoreEnv::new("HOME", original_home);
 
     let command = InitCommand::new();
-    let git_config = command.__get_git_config();
+    let git_config = command.__get_git_config().unwrap();
     assert!(git_config.contains_key("user.name"));
     assert!(git_config.contains_key("user.email"));
 }
diff --git a/crates/shirabe/tests/util/bitbucket_test.rs b/crates/shirabe/tests/util/bitbucket_test.rs
index e0fb9ef2..19641fed 100644
--- a/crates/shirabe/tests/util/bitbucket_test.rs
+++ b/crates/shirabe/tests/util/bitbucket_test.rs
@@ -555,7 +555,11 @@ fn test_get_token_without_access_token() {
 fn test_authorize_oauth_with_wrong_origin_url() {
     let config = ConfigStubBuilder::new().build_shared();
     let mut f = set_up_with_config_and_http(config, vec![]);
-    assert!(!f.bitbucket.authorize_oauth(&format!("non-{}", ORIGIN)));
+    assert!(
+        !f.bitbucket
+            .authorize_oauth(&format!("non-{}", ORIGIN))
+            .unwrap()
+    );
 }
 
 #[test]
@@ -578,7 +582,7 @@ fn test_authorize_oauth_without_available_git_config_token() {
     let mut bitbucket =
         Bitbucket::new(io, config, Some(process), Some(http_downloader), Some(time)).unwrap();
 
-    assert!(!bitbucket.authorize_oauth(ORIGIN));
+    assert!(!bitbucket.authorize_oauth(ORIGIN).unwrap());
 }
 
 #[test]
@@ -595,5 +599,5 @@ fn test_authorize_oauth_with_available_git_config_token() {
     let mut bitbucket =
         Bitbucket::new(io, config, Some(process), Some(http_downloader), Some(time)).unwrap();
 
-    assert!(bitbucket.authorize_oauth(ORIGIN));
+    assert!(bitbucket.authorize_oauth(ORIGIN).unwrap());
 }
diff --git a/crates/shirabe/tests/util/git_test.rs b/crates/shirabe/tests/util/git_test.rs
index 3d447553..448935ec 100644
--- a/crates/shirabe/tests/util/git_test.rs
+++ b/crates/shirabe/tests/util/git_test.rs
@@ -68,10 +68,6 @@ impl ConfigSourceInterface for NullConfigSource {
     }
 }
 
-// PHP's `commandCallable` returns a bare string (`'git command'`); Rust's `run_command`
-// flattens each callable to a `Vec<String>` and hands it to `execute_args`, which always
-// builds a `PhpMixed::List`. So the single-token string command becomes a one-element list,
-// and the corresponding process expectation is a one-element list as well.
 fn build_git(
     io: IOStub,
     config: Config,
diff --git a/crates/shirabe/tests/util/perforce_test.rs b/crates/shirabe/tests/util/perforce_test.rs
index dfeae457..76ea3f8e 100644
--- a/crates/shirabe/tests/util/perforce_test.rs
+++ b/crates/shirabe/tests/util/perforce_test.rs
@@ -823,7 +823,8 @@ fn test_check_server_exists() {
     );
 
     let result =
-        Perforce::check_server_exists("perforce.does.exist:port", &mut process.borrow_mut());
+        Perforce::check_server_exists("perforce.does.exist:port", &mut process.borrow_mut())
+            .unwrap();
     assert!(result);
 }
 
@@ -843,7 +844,8 @@ fn test_check_server_client_error() {
     );
 
     let result =
-        Perforce::check_server_exists("perforce.does.exist:port", &mut process.borrow_mut());
+        Perforce::check_server_exists("perforce.does.exist:port", &mut process.borrow_mut())
+            .unwrap();
     assert!(!result);
 }