refactor: merge internal/sync into internal/garmin, regroup api files and routes

Garmin auth/sync routes move under /api/garmin/*; sync.Service becomes
garmin.Sync with garmin.SyncConfig/ClientConfig; applog becomes
internal/log; the test mock moves into the garmin package as MockClient
(breaking the test-only import cycle the merge created); stale test
URLs and type names updated to match.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/api/client.ts

@@ -80,20 +80,20 @@ export const api = {
       body: JSON.stringify({ display_name: displayName }),
     }),
 
-  // Auth
-  login: () => request<AuthResponse>("/api/auth/login", { method: "POST" }),
-  submitMFA: (code: string) =>
-    request<AuthResponse>("/api/auth/mfa", { method: "POST", body: JSON.stringify({ code }) }),
-  authStatus: () => request<AuthResponse>("/api/auth/status"),
+  // Garmin Auth
+  garminLogin: () => request<AuthResponse>("/api/garmin/auth/login", { method: "POST" }),
+  garminMFA: (code: string) =>
+    request<AuthResponse>("/api/garmin/auth/mfa", { method: "POST", body: JSON.stringify({ code }) }),
+  garminStatus: () => request<AuthResponse>("/api/garmin/auth/status"),
 
-  // Sync
-  syncRun: () => request<{ status: string }>("/api/sync/run", { method: "POST" }),
+  // Garmin Sync
+  garminSyncRun: () => request<{ status: string }>("/api/garmin/sync/run", { method: "POST" }),
   // Deletes every synced activity (and its laps/samples/kind assignments)
   // and rewinds the backfill watermark -- destructive, gated by a
   // confirmation in the UI.
-  resetSync: () => request<{ status: string }>("/api/sync/reset", { method: "POST" }),
-  syncRuns: () => request<SyncRun[]>("/api/sync/runs"),
-  syncStatus: () => request<SyncStatus>("/api/sync/status"),
+  garminSyncReset: () => request<{ status: string }>("/api/garmin/sync/reset", { method: "POST" }),
+  garminSyncRuns: () => request<SyncRun[]>("/api/garmin/sync/runs"),
+  garminSyncStatus: () => request<SyncStatus>("/api/garmin/sync/status"),
 
   // Training types -- fixed taxonomy, no create/delete
   listWorkoutKinds: (includeInactive = false) =>

frontend/src/components/GarminConnection.tsx

@@ -18,9 +18,9 @@ export function GarminConnection({ onBeforeConnect }: { onBeforeConnect?: () =>
   // it's open, so this no longer needs the "poll faster while syncing"
   // dynamic interval it used to have.
   useEffect(() => {
-    api.authStatus().then(setAuth).catch((e) => showError(String(e)));
+    api.garminStatus().then(setAuth).catch((e) => showError(String(e)));
     const interval = setInterval(() => {
-      api.authStatus().then(setAuth).catch(() => {});
+      api.garminStatus().then(setAuth).catch(() => {});
     }, 6000);
     return () => clearInterval(interval);
   }, []);
@@ -29,7 +29,7 @@ export function GarminConnection({ onBeforeConnect }: { onBeforeConnect?: () =>
     setBusy(true);
     try {
       await onBeforeConnect?.();
-      const result = await api.login();
+      const result = await api.garminLogin();
       setAuth(result);
       setDisconnected(false);
       if (result.status === "authenticated") showSuccess("Connected to Garmin successfully.");
@@ -48,7 +48,7 @@ export function GarminConnection({ onBeforeConnect }: { onBeforeConnect?: () =>
     if (!code.trim()) return;
     setBusy(true);
     try {
-      const result = await api.submitMFA(code.trim());
+      const result = await api.garminMFA(code.trim());
       setAuth(result);
       if (result.status === "authenticated") showSuccess("Connected to Garmin successfully.");
     } catch (e) {
@@ -61,7 +61,7 @@ export function GarminConnection({ onBeforeConnect }: { onBeforeConnect?: () =>
   async function sync() {
     setBusy(true);
     try {
-      await api.syncRun();
+      await api.garminSyncRun();
       setShowSyncModal(true);
     } catch (e) {
       showError(String(e));
@@ -76,14 +76,14 @@ export function GarminConnection({ onBeforeConnect }: { onBeforeConnect?: () =>
     }
     setBusy(true);
     try {
-      await api.resetSync();
+      await api.garminSyncReset();
       // Reset runs as a background sync job; wait for it to actually finish
       // before reloading, otherwise other pages (e.g. Activities) would
       // still show the just-deleted activities from their own stale state.
-      let status = await api.syncStatus();
+      let status = await api.garminSyncStatus();
       while (status.in_progress) {
         await new Promise((resolve) => setTimeout(resolve, 300));
-        status = await api.syncStatus();
+        status = await api.garminSyncStatus();
       }
       window.location.reload();
     } catch (e) {

frontend/src/components/SyncModal.tsx

@@ -61,7 +61,7 @@ export function SyncModal({ onClose }: { onClose: () => void }) {
     let timeout: ReturnType<typeof setTimeout>;
     const tick = () => {
       api
-        .syncStatus()
+        .garminSyncStatus()
         .then((s) => {
           setStatus(s);
           if (!s.in_progress) {