fix(#219): add pagination to sessions history tab (#357)

* fix(#219): add pagination to sessions history tab

The /api/sessions endpoint was called without pagination params, so the server returned only its default limit of 20 sessions.

- SessionListResponse: added total/limit/offset fields from server response
- HermesApiService: added @Query params (limit, offset, order) to getSessions()
- SessionsViewModel: added loadMore() that appends pages, hasMore derived from total
- SessionsScreen: added 'Load more sessions' button + loading spinner at bottom of list

* chore: remove plan file from git

* fix: compilation errors in sessions pagination

* chore: gitignore plan files

* fix: remove duplicate brace

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Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/data/remote/HermesApiService.kt

@@ -67,7 +67,11 @@ interface HermesApiService {
     suspend fun getStatus(): Response<StatusResponse>
 
     @GET("api/sessions")
-    suspend fun getSessions(): Response<SessionListResponse>
+    suspend fun getSessions(
+        @Query("limit") limit: Int = 20,
+        @Query("offset") offset: Int = 0,
+        @Query("order") order: String = "recent",
+    ): Response<SessionListResponse>
 
     @GET("api/sessions/{id}/messages")
     suspend fun getSessionMessages(