feat(slash): fondation du système de commandes slash pour la CLI custom — #162 (QA verte)

Introduit le contrat unifié des commandes slash consommable par le frontend,
indépendant de la source (native, puis plugin plus tard) :

- domain: modèle pur SlashCommand / SlashCommandSource / SlashCommandAvailability,
  métadonnées UI (nom, description, disponibilité, confirmation requise) et
  validation des noms/préfixes.
- application: registry + list/filter par préfixe + plan d'exécution natif ;
  commandes natives /help et /clean (/clean = nettoyage de la vue de session
  courante ; pas de /reset distinct tant qu'aucune utilité produit ne le justifie).
- backend + app-tauri: exposition du contrat via DTO/transport + tests DTO.

Source neutre : les commandes contribuées par plugins (#165) transiteront par
le même registry sans changer le contrat frontend.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

crates/app-tauri/src/chat.rs

@@ -93,6 +93,16 @@ impl ChatBridge {
         self.inner.scrollback(session)
     }
 
+    /// Clears only the retained conversation scrollback for a live session,
+    /// keeping any currently attached channel in place.
+    ///
+    /// Returns the number of chunks removed. This powers `/clean`: the frontend
+    /// clears its mounted view from the command response, and future re-attaches
+    /// no longer replay the old conversation.
+    pub fn clear_scrollback(&self, session: &SessionId) -> usize {
+        self.inner.clear_scrollback(session)
+    }
+
     /// Removes a session's transport state **and** its retained scrollback
     /// unconditionally (chat cell explicitly closed). Twin of
     /// [`PtyBridge::unregister`](crate::pty::PtyBridge::unregister).

crates/app-tauri/src/commands.rs

@@ -15,21 +15,23 @@ use application::{
     AppError, AssignSkillToAgentInput, AttachLiveAgentInput, ChangeAgentProfileInput,
     CloseProjectInput, CreateAgentInput, CreateLayoutInput, CreateMemoryInput, CreateSkillInput,
     DeleteAgentInput, DeleteEmbedderProfileInput, DeleteLayoutInput, DeleteMemoryInput,
-    DeleteSkillInput, DeleteTemplateInput, DetectAgentDriftInput, GetMemoryInput,
-    GetProjectSystemPermissionsInput, GetProjectWorkStateInput, GitBranchesInput, GitCheckoutInput,
-    GitCommitInput, GitGraphInput, GitInitInput, GitLogInput, GitStagePathInput, GitStatusInput,
-    InspectConversationInput, LaunchAgentInput, ListAgentsInput, ListDevicesInput,
-    ListLayoutsInput, ListMemoriesInput, ListResumableAgentsInput, ListSkillsInput, LiveSessions,
-    LoadLayoutInput, McpRuntime, MutateLayoutInput, OpenPluginLayoutWindowInput, OpenProjectInput,
-    ReadAgentContextInput, ReadConversationPageInput, ReadMcpToolPermissionsInput,
-    ReadMemoryIndexInput, ReadProjectContextInput, RecallMemoryInput, ReconcileLayoutsInput,
-    ReconcileLiveStateInput, RenameDeviceInput, RenameLayoutInput, ResolveAgentPermissionsInput,
+    DeleteSkillInput, DeleteTemplateInput, DetectAgentDriftInput, ExecuteSlashCommandInput,
+    GetMemoryInput, GetProjectSystemPermissionsInput, GetProjectWorkStateInput, GitBranchesInput,
+    GitCheckoutInput, GitCommitInput, GitGraphInput, GitInitInput, GitLogInput, GitStagePathInput,
+    GitStatusInput, InspectConversationInput, LaunchAgentInput, ListAgentsInput, ListDevicesInput,
+    ListLayoutsInput, ListMemoriesInput, ListResumableAgentsInput, ListSkillsInput,
+    ListSlashCommandsInput, LiveSessions, LoadLayoutInput, McpRuntime, MutateLayoutInput,
+    OpenPluginLayoutWindowInput, OpenProjectInput, ReadAgentContextInput,
+    ReadConversationPageInput, ReadMcpToolPermissionsInput, ReadMemoryIndexInput,
+    ReadProjectContextInput, RecallMemoryInput, ReconcileLayoutsInput, ReconcileLiveStateInput,
+    RenameDeviceInput, RenameLayoutInput, ResolveAgentPermissionsInput,
     ResolveAgentSystemPermissionsInput, ResolveMemoryLinksInput, RevokeDeviceInput,
-    RotateConversationLogInput, SetActiveLayoutInput, SnapshotRunningAgentsInput,
-    StopLiveAgentInput, SyncAgentWithTemplateInput, UnassignSkillFromAgentInput,
-    UpdateAgentContextInput, UpdateAgentEffortInput, UpdateAgentMcpToolPermissionsInput,
-    UpdateAgentPermissionsInput, UpdateAgentSystemPermissionsInput, UpdateMemoryInput,
-    UpdateProjectContextInput, UpdateProjectMcpToolPermissionsInput, UpdateProjectPermissionsInput,
+    RotateConversationLogInput, SetActiveLayoutInput, SlashCommandEffect,
+    SnapshotRunningAgentsInput, StopLiveAgentInput, SyncAgentWithTemplateInput,
+    UnassignSkillFromAgentInput, UpdateAgentContextInput, UpdateAgentEffortInput,
+    UpdateAgentMcpToolPermissionsInput, UpdateAgentPermissionsInput,
+    UpdateAgentSystemPermissionsInput, UpdateMemoryInput, UpdateProjectContextInput,
+    UpdateProjectMcpToolPermissionsInput, UpdateProjectPermissionsInput,
     UpdateProjectSystemPermissionsInput, UpdateSkillInput,
 };
 use backend::stream::OutputSink;
@@ -51,7 +53,8 @@ use crate::dto::{
     CreateProjectRequestDto, CreateSkillRequestDto, CreateTemplateRequestDto,
     DeleteLayoutRequestDto, DeleteLayoutResultDto, DeliveredDelegationRequestDto,
     DetectProfilesRequestDto, DetectProfilesResponseDto, EmbedderEnginesDto, EmbedderProfileDto,
-    EmbedderProfileListDto, ErrorDto, FirstRunStateDto, FrontAttachedRequestDto, GitBranchesDto,
+    EmbedderProfileListDto, ErrorDto, ExecuteSlashCommandRequestDto,
+    ExecuteSlashCommandResponseDto, FirstRunStateDto, FrontAttachedRequestDto, GitBranchesDto,
     GitCheckoutRequestDto, GitCommitDto, GitCommitListDto, GitCommitRequestDto, GitStageRequestDto,
     GitStatusListDto, GraphCommitListDto, HealthRequestDto, HealthResponseDto,
     ImportChatAttachmentsRequestDto, ImportChatAttachmentsResponseDto,
@@ -68,12 +71,12 @@ use crate::dto::{
     ResolvedAgentSystemPermissionsDto, ResumableAgentListDto, SaveEmbedderProfileRequestDto,
     SaveModelServerRequestDto, SaveOpenCodeProviderProfileRequestDto, SaveProfileRequestDto,
     SetActiveLayoutRequestDto, SetActiveLayoutResultDto, SkillDto, SkillListDto,
-    StopLiveAgentRequestDto, StopLiveAgentResponseDto, SyncAgentWithTemplateRequestDto,
-    SyncResultDto, TemplateDto, TemplateListDto, TerminalClosedDto, TerminalSessionDto,
-    TurnPageDto, UnassignSkillRequestDto, UpdateAgentContextRequestDto,
-    UpdateAgentEffortRequestDto, UpdateAgentMcpToolPermissionsRequestDto,
-    UpdateAgentPermissionsRequestDto, UpdateAgentSystemPermissionsRequestDto,
-    UpdateMemoryRequestDto, UpdateProjectContextRequestDto,
+    SlashCommandEffectDto, SlashCommandListDto, StopLiveAgentRequestDto, StopLiveAgentResponseDto,
+    SyncAgentWithTemplateRequestDto, SyncResultDto, TemplateDto, TemplateListDto,
+    TerminalClosedDto, TerminalSessionDto, TurnPageDto, UnassignSkillRequestDto,
+    UpdateAgentContextRequestDto, UpdateAgentEffortRequestDto,
+    UpdateAgentMcpToolPermissionsRequestDto, UpdateAgentPermissionsRequestDto,
+    UpdateAgentSystemPermissionsRequestDto, UpdateMemoryRequestDto, UpdateProjectContextRequestDto,
     UpdateProjectMcpToolPermissionsRequestDto, UpdateProjectPermissionsRequestDto,
     UpdateProjectSystemPermissionsRequestDto, UpdateSkillRequestDto, UpdateTemplateRequestDto,
     WriteTerminalRequestDto,
@@ -105,6 +108,69 @@ pub fn health(
         .map_err(ErrorDto::from)
 }
 
+/// `list_slash_commands` — list/filter the unified slash-command registry.
+#[tauri::command]
+pub fn list_slash_commands(
+    request: Option<crate::dto::ListSlashCommandsRequestDto>,
+    state: State<'_, AppState>,
+) -> SlashCommandListDto {
+    let request = request.unwrap_or_default();
+    state
+        .list_slash_commands
+        .execute(ListSlashCommandsInput {
+            prefix: request.prefix,
+        })
+        .into()
+}
+
+/// `execute_slash_command` — execute a selected slash command.
+///
+/// # Errors
+/// Returns an [`ErrorDto`] (`INVALID` for unavailable commands/missing context,
+/// `NOT_FOUND` for unknown commands or closed sessions).
+#[tauri::command]
+pub fn execute_slash_command(
+    request: ExecuteSlashCommandRequestDto,
+    state: State<'_, AppState>,
+) -> Result<ExecuteSlashCommandResponseDto, ErrorDto> {
+    let session_id = request
+        .session_id
+        .as_deref()
+        .map(parse_session_id)
+        .transpose()?;
+    let output = state
+        .execute_slash_command
+        .execute(ExecuteSlashCommandInput {
+            name: request.name,
+            session_id,
+        })
+        .map_err(ErrorDto::from)?;
+
+    let effect = match output.effect {
+        SlashCommandEffect::Help { commands } => SlashCommandEffectDto::Help { commands },
+        SlashCommandEffect::CleanConversation { session_id } => {
+            if state.structured_sessions.session(&session_id).is_none() {
+                return Err(ErrorDto::from(AppError::NotFound(format!(
+                    "structured session {session_id}"
+                ))));
+            }
+            let cleared_chunks = state.chat_bridge.clear_scrollback(&session_id);
+            SlashCommandEffectDto::CleanConversation {
+                session_id: session_id.to_string(),
+                cleared_chunks,
+            }
+        }
+        SlashCommandEffect::ProfileSwitch { session_id } => SlashCommandEffectDto::ProfileSwitch {
+            session_id: session_id.to_string(),
+        },
+    };
+
+    Ok(ExecuteSlashCommandResponseDto {
+        command: output.command,
+        effect,
+    })
+}
+
 /// `get_server_exposure_settings` — read persisted embedded-server exposure settings.
 ///
 /// # Errors

crates/app-tauri/src/lib.rs

@@ -248,6 +248,8 @@ pub fn run() {
         })
         .invoke_handler(tauri::generate_handler![
             commands::health,
+            commands::list_slash_commands,
+            commands::execute_slash_command,
             commands::create_project,
             commands::open_project,
             commands::close_project,