feat(#444): MCP tab parity — add servers, catalog, env vars, restart, diagnostics (#462)

* feat(#444): add MCP API endpoints and data models

- Add McpServer.status and McpServer.error fields for diagnostics
- Add AddMcpServerRequest, McpCatalogResponse/Entry/EnvVar models
- Add McpServerTestResponse model
- Add POST addMcpServer, PUT updateMcpServer, POST restartMcpServer
- Add GET getMcpCatalog, POST installMcpCatalogEntry

* feat(#444): add server form, enriched server cards, catalog section

- Add HTTP/stdio inline server form with tabs
- Enriched server cards with status badge, restart, env var editing
- Add/edit/remove environment variables per server
- Catalog section with search, result cards, install flow with env vars
- Status badge colors: running=green, error=red, stopped/gray
- Server diagnostics shown as error badges on cards
- New string resources for all MCP UI elements

* fix(#444): add missing McpServer import to HermesApiService

* fix(#444): cleanup review issues — dead code, spinner, unused strings

- Remove unused serverDiagnostics from UiState
- Remove unused showDiagnostics local state in ServerCard
- Remove unused McpServerTestResponse model
- Remove redundant refreshDiagnostics() alias
- Replace catalog loading text with CircularProgressIndicator
- Remove unused string resources (action_restarting, diagnostics, catalog_load)

* fix(#444): remove remaining showDiagnostics reference at line 348

---------

Co-authored-by: Hermes Agent <hermes@agent.local>

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

@@ -5,6 +5,7 @@ import com.m57.hermescontrol.data.model.AchievementsResponse
 import com.m57.hermescontrol.data.model.ActionResponse
 import com.m57.hermescontrol.data.model.ActionStatusResponse
 import com.m57.hermescontrol.data.model.ActiveProfileResponse
+import com.m57.hermescontrol.data.model.AddMcpServerRequest
 import com.m57.hermescontrol.data.model.AgentPluginInstallBody
 import com.m57.hermescontrol.data.model.AuxiliaryModelsResponse
 import com.m57.hermescontrol.data.model.BulkDeleteRequest
@@ -32,6 +33,9 @@ import com.m57.hermescontrol.data.model.KanbanBoardResponse
 import com.m57.hermescontrol.data.model.KanbanBoardsResponse
 import com.m57.hermescontrol.data.model.KanbanTask
 import com.m57.hermescontrol.data.model.LogResponse
+import com.m57.hermescontrol.data.model.McpCatalogInstallRequest
+import com.m57.hermescontrol.data.model.McpCatalogResponse
+import com.m57.hermescontrol.data.model.McpServer
 import com.m57.hermescontrol.data.model.McpServerToggleRequest
 import com.m57.hermescontrol.data.model.McpServersResponse
 import com.m57.hermescontrol.data.model.MemoryResponse
@@ -334,6 +338,30 @@ interface HermesApiService {
         @Path("name") name: String,
     ): Response<Unit>
 
+    @POST("api/mcp/servers")
+    suspend fun addMcpServer(
+        @Body body: AddMcpServerRequest,
+    ): Response<McpServer>
+
+    @PUT("api/mcp/servers/{name}")
+    suspend fun updateMcpServer(
+        @Path("name") name: String,
+        @Body body: Map<String, Any>,
+    ): Response<McpServer>
+
+    @POST("api/mcp/servers/{name}/restart")
+    suspend fun restartMcpServer(
+        @Path("name") name: String,
+    ): Response<Unit>
+
+    @GET("api/mcp/catalog")
+    suspend fun getMcpCatalog(): Response<McpCatalogResponse>
+
+    @POST("api/mcp/catalog/install")
+    suspend fun installMcpCatalogEntry(
+        @Body body: McpCatalogInstallRequest,
+    ): Response<Map<String, Any>>
+
     @GET("api/webhooks")
     suspend fun getWebhooks(): Response<WebhooksResponse>