refactor(tests): migrate remaining batches to tests/common/

Finishes the lift of shared helpers into `tests/common/`. Covered:
- health, web, oneliners_api, upload (31 tests; upload exercises the
  new `multipart_upload_body` helper driven by doctate_common field
  constants)
- sse_integration, sse_cleanup, transcribe, oneliner_heal_decoupled,
  silent_case_empty, failed_only_case_empty_oneliner,
  transient_failure_retries (24 tests)

Also applied cargo fmt across the test tree and fixed one clippy
needless_borrows_for_generic_args warning in analyze_test.

All 387 tests pass; 3 ignored (as before).

Side effect: health_test previously used a hardcoded `/tmp/doctate-test`
data path, which parallel `cargo test` runs could collide on. The
migration replaces it with the common unique-tmpdir pattern, removing
a latent flake.

server/tests/common/config.rs

@@ -129,9 +129,7 @@ impl TestConfig {
     /// `Config::test_default` themselves are broken (not reachable in
     /// practice).
     pub fn build(self) -> Arc<Config> {
-        let data_path = self
-            .data_path
-            .unwrap_or_else(|| unique_tmpdir(self.label));
+        let data_path = self.data_path.unwrap_or_else(|| unique_tmpdir(self.label));
         let api_keys: HashMap<String, String> = self
             .users
             .iter()

server/tests/common/http.rs

@@ -121,11 +121,7 @@ pub fn header_str(response: &Response, name: &str) -> String {
 /// Uses the server's canonical field names (`case_id`, `recorded_at`,
 /// `audio`) from `doctate_common::constants`, so a server-side rename
 /// propagates here for free.
-pub fn multipart_upload_body(
-    case_id: &str,
-    recorded_at: &str,
-    audio: &[u8],
-) -> (String, Vec<u8>) {
+pub fn multipart_upload_body(case_id: &str, recorded_at: &str, audio: &[u8]) -> (String, Vec<u8>) {
     let boundary = "----testboundary";
     let mut body = Vec::new();
 

server/tests/common/mod.rs

@@ -26,7 +26,7 @@ pub mod users;
 // Re-exports for ergonomic `use common::*;` in most test files.
 pub use config::{TestConfig, unique_tmpdir};
 pub use http::{
-    body_json, body_string, csrf_form_post, form_post, get_with_api_key,
+    body_bytes, body_json, body_string, csrf_form_post, form_post, get_with_api_key,
     get_with_api_key_if_none_match, get_with_cookie, header_opt, header_str, multipart_upload_body,
 };
 pub use seed::{

server/tests/common/seed.rs

@@ -40,11 +40,7 @@ pub fn seed_recording(case_dir: &Path, stem: &str, transcript: Option<&str>) ->
 /// Like [`seed_recording`] but additionally writes the `.duration.txt`
 /// sidecar — used by the delete-recording tests that assert every
 /// sidecar is cleaned up.
-pub fn seed_recording_with_sidecars(
-    case_dir: &Path,
-    stem: &str,
-    transcript: &str,
-) -> String {
+pub fn seed_recording_with_sidecars(case_dir: &Path, stem: &str, transcript: &str) -> String {
     let filename = seed_recording(case_dir, stem, Some(transcript));
     std::fs::write(case_dir.join(format!("{stem}.duration.txt")), "42").unwrap();
     filename

server/tests/common/users.rs

@@ -58,11 +58,7 @@ pub fn test_user_with_password(slug: &str, password: &str) -> User {
 
 /// Doctor user with custom retention settings — for the retention sweep
 /// tests that drive the lazy auto-close / auto-purge logic.
-pub fn test_user_with_retention(
-    slug: &str,
-    auto_close_days: u32,
-    auto_delete_days: u32,
-) -> User {
+pub fn test_user_with_retention(slug: &str, auto_close_days: u32, auto_delete_days: u32) -> User {
     let mut u = test_user(slug);
     u.retention = RetentionUserSettings {
         auto_close_days,