feat(biz): add wx biz-articles command to query public account messages

PR_DRAFT.md

@@ -0,0 +1,126 @@
+# feat(biz): add `wx biz-articles` command to query public account messages
+
+## Summary
+
+Adds a new `biz-articles` subcommand that queries locally cached WeChat public account (公众号) article pushes from `biz_message_0.db`.
+
+This enables a downstream workflow for downloading full article content:
+
+```bash
+wx biz-articles --since today --json | jq '.[].url' | xargs opencli weixin download
+```
+
+## Background
+
+- WeChat stores public account (官方账号) message pushes in a separate database: `message/biz_message_0.db` (SQLCipher 4 encrypted)
+- This DB was not exposed by any existing wx-cli command
+- The encryption key is already scanned and stored in `~/.wx-cli/all_keys.json` by `wx init`
+- Each public account has its own `Msg_{md5(username)}` table, following the same convention as `message_0.db`
+- Message content is zstd-compressed XML containing `<mmreader>/<item>` structures with article metadata
+
+## New CLI Interface
+
+```bash
+# Last 50 articles (default)
+wx biz-articles
+
+# More articles
+wx biz-articles -n 200
+
+# Filter by public account name (fuzzy match on display name)
+wx biz-articles --account "返朴"
+wx biz-articles --account "Datawhale"
+
+# Time filter (article publish time, YYYY-MM-DD)
+wx biz-articles --since 2026-05-10
+wx biz-articles --since 2026-05-01 --until 2026-05-10
+
+# Show only accounts with unread messages, one latest article per account
+wx biz-articles --unread
+wx biz-articles --unread --account "Datawhale"   # combine: unread within specific account
+
+# JSON output (for downstream piping)
+wx biz-articles --json
+wx biz-articles --since 2026-05-10 --json | jq '.[].url'
+```
+
+## Output Fields
+
+Each article item includes:
+
+| Field | Description |
+|-------|-------------|
+| `time` | Article publish time (formatted) |
+| `timestamp` | Article publish timestamp (seconds) |
+| `recv_time` | Message receive time (when WeChat pushed it) |
+| `recv_time_str` | Message receive time (formatted) |
+| `account` | Public account display name |
+| `account_username` | Public account username (gh_*) |
+| `title` | Article title |
+| `url` | Article URL (mp.weixin.qq.com link) |
+| `digest` | Article summary/excerpt |
+| `cover_url` | Cover image URL |
+
+## Implementation Notes
+
+- `biz_message_0.db` is loaded on-demand via existing `DbCache` mechanism (no startup cost unless `biz-articles` is called)
+- The key for `message/biz_message_0.db` is already in `all_keys.json`, no changes to `wx init` needed
+- Multi-article pushes (图文消息) are expanded: each `<item>` in `<mmreader>` becomes a separate output row
+- Items without URL or title (e.g., payment notifications from service accounts) are filtered out
+- New `extract_cdata` helper function strips CDATA wrappers from XML content
+- Results sorted by `pub_time` DESC (article publish time, not message receive time)
+
+### `--unread` semantics
+
+- Queries `session.db` for `unread_count > 0` rows whose `chat_type == official_account`, intersects with `--account` filter if both provided
+- Returns at most **one latest article per account** (dedupe by `account_username` after the global pub_time DESC sort)
+- Aligns with the behavior of `wx unread --filter official` for fast "what unread accounts are there + what's the latest title" scanning
+- Empty intersection short-circuits before scanning biz tables
+
+## Changes
+
+- `src/ipc.rs`: Add `BizArticles` IPC request variant
+- `src/cli/biz_articles.rs`: New CLI command handler (follows sns_feed pattern)  
+- `src/cli/mod.rs`: Register `BizArticles` subcommand in clap + dispatch
+- `src/daemon/query.rs`: Add `q_biz_articles` query + `parse_biz_xml_items` + `extract_cdata` helpers + 8 unit tests
+- `src/daemon/server.rs`: Add dispatch case for `BizArticles`
+
+## Test Results
+
+```
+test result: ok. 49 passed; 0 failed; 0 ignored
+```
+
+New tests (8):
+- `biz_tests::extract_cdata_normal`
+- `biz_tests::extract_cdata_empty`
+- `biz_tests::extract_cdata_url`
+- `biz_tests::extract_cdata_no_cdata_wrapper`
+- `biz_tests::parse_biz_xml_items_single_article`
+- `biz_tests::parse_biz_xml_items_skips_no_url`
+- `biz_tests::parse_biz_xml_items_multi_article`
+- `biz_tests::parse_biz_xml_items_pub_time_fallback`
+
+## Verified Output (real WeChat install with ~30 public accounts, 2026-05-10)
+
+```yaml
+- account: 返朴
+  title: 细胞生物学家俞立：从后进生到科学家，一个ADHD孩子的逆袭
+  url: http://mp.weixin.qq.com/s?__biz=Mzg2MTUyODU2NA==&mid=2247642795&...
+
+- account: Datawhale
+  title: 刚刚，Claude Code 团队这篇文章爆了！
+  url: http://mp.weixin.qq.com/s?__biz=MzIyNjM2MzQyNg==&mid=2247722630&...
+
+- account: 土猛的员外
+  title: AI时代，企业的业务底座正在从数据库变成知识引擎
+  url: http://mp.weixin.qq.com/s?__biz=MzIyOTA5NTM1OA==&mid=2247485270&...
+```
+
+## Branch
+
+`ChenyqThu/wx-cli` → `feat/biz-articles`
+
+---
+
+*Waiting for Lucien's review before opening PR.*

src/cli/biz_articles.rs

@@ -0,0 +1,30 @@
+use anyhow::Result;
+use crate::ipc::Request;
+use super::history::{parse_time, parse_time_end};
+use super::transport;
+use super::output::{resolve, print_value};
+
+pub fn cmd_biz_articles(
+    limit: usize,
+    account: Option<String>,
+    since: Option<String>,
+    until: Option<String>,
+    unread: bool,
+    json: bool,
+) -> Result<()> {
+    let since_ts = since.as_deref().map(parse_time).transpose()?;
+    let until_ts = until.as_deref().map(parse_time_end).transpose()?;
+
+    let req = Request::BizArticles {
+        limit,
+        account,
+        since: since_ts,
+        until: until_ts,
+        unread,
+    };
+    let resp = transport::send(req)?;
+    let data = resp.data.get("articles")
+        .cloned()
+        .unwrap_or(serde_json::Value::Array(vec![]));
+    print_value(&data, &resolve(json))
+}

src/cli/mod.rs

@@ -1,4 +1,5 @@
 mod init;
+pub mod biz_articles;
 pub mod sessions;
 pub mod history;
 pub mod search;
@@ -220,6 +221,27 @@ enum Commands {
         #[arg(long)]
         json: bool,
     },
+    /// 查询公众号文章推送（本地缓存）
+    BizArticles {
+        /// 显示数量
+        #[arg(short = 'n', long, default_value = "50")]
+        limit: usize,
+        /// 限定公众号（名称模糊匹配）
+        #[arg(long)]
+        account: Option<String>,
+        /// 起始时间 YYYY-MM-DD
+        #[arg(long)]
+        since: Option<String>,
+        /// 结束时间 YYYY-MM-DD
+        #[arg(long)]
+        until: Option<String>,
+        /// 只看有未读的公众号，每个公众号取最新 1 篇
+        #[arg(long)]
+        unread: bool,
+        /// 输出 JSON（默认 YAML）
+        #[arg(long)]
+        json: bool,
+    },
     /// 朋友圈全文搜索：匹配正文关键词
     SnsSearch {
         /// 关键词
@@ -304,6 +326,9 @@ fn dispatch(cli: Cli) -> Result<()> {
         Commands::SnsSearch { keyword, limit, since, until, user, json } => {
             sns_search::cmd_sns_search(keyword, limit, since, until, user, json)
         }
+        Commands::BizArticles { limit, account, since, until, unread, json } => {
+            biz_articles::cmd_biz_articles(limit, account, since, until, unread, json)
+        }
         Commands::Daemon { cmd } => daemon_cmd::cmd_daemon(cmd),
     }
 }