feat(ui): hide observer-sessions project from UI lists

Observer sessions (internal SDK-driven worker queries) run under a
synthetic project name 'observer-sessions' to keep them out of
claude --resume. They were still surfacing in the viewer project
picker and unfiltered observation/summary/prompt feeds.

Filter them out at every UI-facing query:
- SessionStore.getAllProjects and getProjectCatalog
- timeline/queries.ts getAllProjects
- PaginationHelper observations/summaries/prompts when no project is selected

When a caller explicitly requests project='observer-sessions',
results are still returned (not a hard ban, just hidden by default).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/services/sqlite/SessionStore.ts

@@ -1192,6 +1192,7 @@ export class SessionStore {
       SELECT DISTINCT project
       FROM sdk_sessions
       WHERE project IS NOT NULL AND project != ''
+        AND project != 'observer-sessions'
     `;
     const params: unknown[] = [];
 
@@ -1218,6 +1219,7 @@ export class SessionStore {
         MAX(started_at_epoch) as latest_epoch
       FROM sdk_sessions
       WHERE project IS NOT NULL AND project != ''
+        AND project != 'observer-sessions'
       GROUP BY COALESCE(platform_source, '${DEFAULT_PLATFORM_SOURCE}'), project
       ORDER BY latest_epoch DESC
     `).all() as Array<{ platform_source: string; project: string; latest_epoch: number }>;

src/services/sqlite/timeline/queries.ts

@@ -210,6 +210,7 @@ export function getAllProjects(db: Database): string[] {
     SELECT DISTINCT project
     FROM sdk_sessions
     WHERE project IS NOT NULL AND project != ''
+      AND project != 'observer-sessions'
     ORDER BY project ASC
   `);
 

src/services/worker/PaginationHelper.ts

@@ -105,6 +105,9 @@ export class PaginationHelper {
       // surfaces observations that originated under its merged children.
       conditions.push('(o.project = ? OR o.merged_into_project = ?)');
       params.push(project, project);
+    } else {
+      // Hide internal observer-session rows from the unfiltered UI list.
+      conditions.push("o.project != 'observer-sessions'");
     }
     if (platformSource) {
       conditions.push(`COALESCE(s.platform_source, 'claude') = ?`);
@@ -163,6 +166,9 @@ export class PaginationHelper {
       // surfaces rows that originated under its merged children.
       conditions.push('(ss.project = ? OR ss.merged_into_project = ?)');
       params.push(project, project);
+    } else {
+      // Hide internal observer-session rows from the unfiltered UI list.
+      conditions.push("ss.project != 'observer-sessions'");
     }
 
     if (platformSource) {
@@ -214,6 +220,9 @@ export class PaginationHelper {
     if (project) {
       conditions.push('s.project = ?');
       params.push(project);
+    } else {
+      // Hide internal observer-session rows from the unfiltered UI list.
+      conditions.push("s.project != 'observer-sessions'");
     }
 
     if (platformSource) {

src/shared/paths.ts

@@ -75,6 +75,10 @@ export const VECTOR_DB_DIR = join(DATA_DIR, 'vector-db');
 // Sessions here won't appear in user's `claude --resume` for their actual projects
 export const OBSERVER_SESSIONS_DIR = join(DATA_DIR, 'observer-sessions');
 
+// Project name assigned to observer sessions (basename of OBSERVER_SESSIONS_DIR).
+// UI queries filter this out so internal worker sessions don't pollute project lists.
+export const OBSERVER_SESSIONS_PROJECT = 'observer-sessions';
+
 // Claude integration paths
 export const CLAUDE_SETTINGS_PATH = join(CLAUDE_CONFIG_DIR, 'settings.json');
 export const CLAUDE_COMMANDS_DIR = join(CLAUDE_CONFIG_DIR, 'commands');