feat: add full-text search across conversations (#482)

* feat: add full-text search across conversations in sidebar

Add a search mode toggle (Projects/Conversations) to the sidebar search bar.
In Conversations mode, search text content across all JSONL session files
with debounced API calls, highlighted snippets, and click-to-navigate results.

* fix: address PR review feedback - session summary tracking, search sequence invalidation, fallback navigation, SSE streaming

- Track session summaries per-session in a Map instead of file-scoped variable
- Increment searchSeqRef when clearing conversation search to invalidate in-flight requests
- Add fallback session navigation when session not loaded in sidebar paging
- Stream search results via SSE for progressive display with progress indicator

* feat(search): add Codex/Gemini search and scroll-to-message navigation

- Search now includes Codex sessions (JSONL from ~/.codex/sessions/) and
  Gemini sessions (in-memory via sessionManager) in addition to Claude
- Search results include provider info and display a provider badge
- Click handler resolves the correct provider instead of hardcoding claude
- Clicking a search result loads all messages and scrolls to the matched
  message with a highlight flash animation

* fix(search): Codex search path matching and scroll reliability

- Fix Codex search scanning all sessions for every project by checking
  session_meta cwd match BEFORE scanning messages (was inflating match
  count and hitting limit before reaching later projects)
- Fix Codex search missing user messages in response_item entries
  (role=user with input_text content parts)
- Fix scroll-to-message being overridden by initial scrollToBottom
  using searchScrollActiveRef to inhibit competing scroll effects
- Fix snippet matching using contiguous substring instead of
  filtered words (which created non-existent phrases)

* feat(search): add Gemini CLI session support for search and history viewing

Gemini CLI sessions stored in ~/.gemini/tmp/<project>/chats/*.json are now
indexed for conversation search and can be loaded for viewing. Previously
only sessions created through the UI (sessionManager) were searchable.

* fix(search): full-word matching and longer highlight flash

- Search now uses word boundaries (\b) instead of substring matching,
  so "hi" no longer matches "this"
- Highlight flash extended to 4s with thicker outline and subtle
  background tint for better visibility

src/components/sidebar/hooks/useSidebarController.ts

@@ -1,4 +1,5 @@
-import { useCallback, useEffect, useMemo, useState } from 'react';
+import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
+import type React from 'react';
 import type { TFunction } from 'i18next';
 import { api } from '../../../utils/api';
 import type { Project, ProjectSession, SessionProvider } from '../../../types/app';
@@ -19,6 +20,44 @@ import {
   sortProjects,
 } from '../utils/utils';
 
+type SnippetHighlight = {
+  start: number;
+  end: number;
+};
+
+type ConversationMatch = {
+  role: string;
+  snippet: string;
+  highlights: SnippetHighlight[];
+  timestamp: string | null;
+  provider?: string;
+  messageUuid?: string | null;
+};
+
+type ConversationSession = {
+  sessionId: string;
+  sessionSummary: string;
+  provider?: string;
+  matches: ConversationMatch[];
+};
+
+type ConversationProjectResult = {
+  projectName: string;
+  projectDisplayName: string;
+  sessions: ConversationSession[];
+};
+
+export type ConversationSearchResults = {
+  results: ConversationProjectResult[];
+  totalMatches: number;
+  query: string;
+};
+
+export type SearchProgress = {
+  scannedProjects: number;
+  totalProjects: number;
+};
+
 type UseSidebarControllerArgs = {
   projects: Project[];
   selectedProject: Project | null;
@@ -71,6 +110,13 @@ export function useSidebarController({
   const [sessionDeleteConfirmation, setSessionDeleteConfirmation] = useState<SessionDeleteConfirmation | null>(null);
   const [showVersionModal, setShowVersionModal] = useState(false);
   const [starredProjects, setStarredProjects] = useState<Set<string>>(() => loadStarredProjects());
+  const [searchMode, setSearchMode] = useState<'projects' | 'conversations'>('projects');
+  const [conversationResults, setConversationResults] = useState<ConversationSearchResults | null>(null);
+  const [isSearching, setIsSearching] = useState(false);
+  const [searchProgress, setSearchProgress] = useState<SearchProgress | null>(null);
+  const searchTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const searchSeqRef = useRef(0);
+  const eventSourceRef = useRef<EventSource | null>(null);
 
   const isSidebarCollapsed = !isMobile && !sidebarVisible;
 
@@ -140,6 +186,116 @@ export function useSidebarController({
     };
   }, []);
 
+  // Debounced conversation search with SSE streaming
+  useEffect(() => {
+    if (searchTimeoutRef.current) {
+      clearTimeout(searchTimeoutRef.current);
+    }
+    if (eventSourceRef.current) {
+      eventSourceRef.current.close();
+      eventSourceRef.current = null;
+    }
+
+    const query = searchFilter.trim();
+    if (searchMode !== 'conversations' || query.length < 2) {
+      searchSeqRef.current += 1;
+      setConversationResults(null);
+      setSearchProgress(null);
+      setIsSearching(false);
+      return;
+    }
+
+    setIsSearching(true);
+    const seq = ++searchSeqRef.current;
+
+    searchTimeoutRef.current = setTimeout(() => {
+      if (seq !== searchSeqRef.current) return;
+
+      const url = api.searchConversationsUrl(query);
+      const es = new EventSource(url);
+      eventSourceRef.current = es;
+
+      const accumulated: ConversationProjectResult[] = [];
+      let totalMatches = 0;
+
+      es.addEventListener('result', (evt) => {
+        if (seq !== searchSeqRef.current) { es.close(); return; }
+        try {
+          const data = JSON.parse(evt.data) as {
+            projectResult: ConversationProjectResult;
+            totalMatches: number;
+            scannedProjects: number;
+            totalProjects: number;
+          };
+          accumulated.push(data.projectResult);
+          totalMatches = data.totalMatches;
+          setConversationResults({ results: [...accumulated], totalMatches, query });
+          setSearchProgress({ scannedProjects: data.scannedProjects, totalProjects: data.totalProjects });
+        } catch {
+          // Ignore malformed SSE data
+        }
+      });
+
+      es.addEventListener('progress', (evt) => {
+        if (seq !== searchSeqRef.current) { es.close(); return; }
+        try {
+          const data = JSON.parse(evt.data) as { totalMatches: number; scannedProjects: number; totalProjects: number };
+          totalMatches = data.totalMatches;
+          setSearchProgress({ scannedProjects: data.scannedProjects, totalProjects: data.totalProjects });
+        } catch {
+          // Ignore malformed SSE data
+        }
+      });
+
+      es.addEventListener('done', () => {
+        if (seq !== searchSeqRef.current) { es.close(); return; }
+        es.close();
+        eventSourceRef.current = null;
+        setIsSearching(false);
+        setSearchProgress(null);
+        if (accumulated.length === 0) {
+          setConversationResults({ results: [], totalMatches: 0, query });
+        }
+      });
+
+      es.addEventListener('error', () => {
+        if (seq !== searchSeqRef.current) { es.close(); return; }
+        es.close();
+        eventSourceRef.current = null;
+        setIsSearching(false);
+        setSearchProgress(null);
+        if (accumulated.length === 0) {
+          setConversationResults({ results: [], totalMatches: 0, query });
+        }
+      });
+    }, 400);
+
+    return () => {
+      if (searchTimeoutRef.current) {
+        clearTimeout(searchTimeoutRef.current);
+      }
+      if (eventSourceRef.current) {
+        eventSourceRef.current.close();
+        eventSourceRef.current = null;
+      }
+    };
+  }, [searchFilter, searchMode]);
+
+  const handleTouchClick = useCallback(
+    (callback: () => void) =>
+      (event: React.TouchEvent<HTMLElement>) => {
+        const target = event.target as HTMLElement;
+        if (target.closest('.overflow-y-auto') || target.closest('[data-scroll-container]')) {
+          return;
+        }
+
+        event.preventDefault();
+        event.stopPropagation();
+        callback();
+      },
+    [],
+  );
+
   const toggleProject = useCallback((projectName: string) => {
     setExpandedProjects((prev) => {
       const next = new Set<string>();
@@ -466,6 +622,21 @@ export function useSidebarController({
     setEditingName,
     setEditingSession,
     setEditingSessionName,
+    searchMode,
+    setSearchMode,
+    conversationResults,
+    isSearching,
+    searchProgress,
+    clearConversationResults: useCallback(() => {
+      searchSeqRef.current += 1;
+      if (eventSourceRef.current) {
+        eventSourceRef.current.close();
+        eventSourceRef.current = null;
+      }
+      setIsSearching(false);
+      setSearchProgress(null);
+      setConversationResults(null);
+    }, []),
     setSearchFilter,
     setDeleteConfirmation,
     setSessionDeleteConfirmation,