#19254: fix(feishu): honor wildcard group config for reply policy

## Summary Fix Feishu group wildcard policy handling so `channels.feishu.groups["*"]` is applied when a specific group ID entry is missing. Without this fallback, wildcard group settings (for example `requireMention: false`) are ignored for unmatched groups, causing group behavior to unexpectedly fall back to global defaults. ## Changes - `extensions/feishu/src/policy.ts` - In `resolveFeishuGroupConfig`, return the wildcard group config (`groups["*"]`) when no exact/case-insensitive match exists. - `extensions/feishu/src/policy.test.ts` (new) - Added tests for: - wildcard fallback when direct group config is absent - exact match taking precedence over wildcard - case-insensitive explicit group ID matching still working ## Repro 1. Configure: - `channels.feishu.groups["*"].requireMention = false` - no explicit entry for a target group 2. Send a group message without mentioning the bot. ### Before The wildcard was not applied; message could still be treated as mention-gated. ### After The wildcard config is applied; behavior follows `groups["*"]` as expected. ## Validation - Ran: - `pnpm exec vitest run --config vitest.extensions.config.ts extensions/feishu/src/policy.test.ts` - Result: - `1 passed`, `3 passed` <!-- greptile_comment --> <h3>Greptile Summary</h3> Adds wildcard fallback logic to `resolveFeishuGroupConfig` so that `channels.feishu.groups["*"]` configuration is properly applied when no explicit group ID match exists. This fixes unintended fallback to global defaults for unconfigured groups. - **Logic change**: Returns wildcard config (`groups["*"]`) after exhausting exact and case-insensitive matching - **Test coverage**: Added comprehensive tests validating wildcard fallback, precedence rules, and case-insensitive matching - **Consistency**: Aligns with similar wildcard patterns in other channel extensions (e.g., IRC) <h3>Confidence Score: 5/5</h3> - This PR is safe to merge with minimal risk - The change is simple, well-tested, and follows established patterns in the codebase. The logic correctly implements wildcard fallback with proper precedence (exact > case-insensitive > wildcard). Tests cover all critical paths including edge cases. - No files require special attention _{Last reviewed commit: 2e8ec64} <!-- greptile_other_comments_section --> _{(3/5) Reply to the agent's comments like "Can you suggest a fix for this @greptileai?" or ask follow-up questions!} <!-- /greptile_comment -->