[Feature Request] Wildcard & Fuzzy Search Support

[HubEight]

Problem

Currently, AFFiNE's search only supports exact keyword matching. Users cannot:

• Search with wildcards (*est → test, best, request)
• Find variations of terms (test → test, testing, tester)
• Use pattern matching for flexible searches

This limitation makes it difficult to find content when you don't remember the exact wording or need to search for word families.

Proposed Solution

Implement two complementary search enhancements:

1. Wildcard Support

• * for multiple characters: *test finds "unittest", "test", "retest"
• ? for single character: t?st finds "test", "tost", "tast"
• Regex patterns for advanced users: /\d{4}/ finds all 4-digit numbers

Examples:

• *est → matches test, best, request, nest
• test* → matches test, testing, tester, tested
• ?est → matches best, rest, test, nest
• proj*2024 → matches project2024, projects2024

2. Fuzzy Search

• Automatic typo tolerance: tset → test
• Similarity matching: "meetng" finds "meeting"
• Configurable sensitivity level (Levenshtein distance)

Use Cases

Research & Documentation:
"I remember writing about 'testing' but can't recall if I used 'test', 'tests', or 'testing'"
→ Search *test* finds all variants

Project Management:
"Find all meeting notes from Q4"
→ meeting*2024 returns all matching entries

Data Analysis:
"Find all project IDs starting with PRJ-"
→ PRJ-* returns all matching entries

Typo Tolerance:
Quickly typed notes with typos like "meeitng" should still match "meeting"
→ Fuzzy search handles this automatically

Multi-language Content:
Users working in multiple languages need flexible pattern matching
→ *test* finds "testing", "getestet", "tester", "Testdaten"

Technical Notes

AFFiNE already uses Manticore Search as backend (since v0.22/0.23), which supports:

• Wildcard operators (*, ?, %)
• Regex patterns (RE2 syntax)
• Configuration options: min_infix_len, min_prefix_len

The feature would primarily need:

1. Frontend integration in the Cmd/Ctrl+K search UI
2. Query parser to detect and process wildcard operators
3. UI indicator showing that wildcards are enabled
4. Documentation with search syntax examples

Comparison with Competitors

| Feature | AFFiNE | Obsidian |
|---------|--------|----------|--------|
| Wildcard Search | ❌ No | ✅ Yes (via regex) |
| Fuzzy Search | ❌ No | ✅ Yes |
| Regex Support | ❌ No | ✅ Yes |

Obsidian offers full regex support via /pattern/ syntax and has become the standard for power users.

Priority Rationale

This feature would:
✅ Significantly improve user experience for knowledge workers
✅ Leverage existing backend capabilities (Manticore)
✅ Align AFFiNE with competitor feature sets
✅ Enable professional research and documentation workflows
✅ Reduce friction for users migrating from Obsidian