feat: add streamd daily command

`streamd daily [YYYYMMDD]` opens the earliest existing daily file
(file_type=daily) whose timestamp falls within the target date.
If no such file exists it creates `<timestamp>_daily.md` and opens it.
Date defaults to today in the repository timezone.

src/cli/commands/daily.rs

@@ -0,0 +1,100 @@
+use std::fs;
+use std::path::Path;
+use std::process::Command;
+
+use chrono::{Days, NaiveDate, NaiveDateTime, NaiveTime, TimeZone, Utc};
+use chrono_tz::Tz;
+use walkdir::WalkDir;
+
+use crate::config::Settings;
+use crate::error::StreamdError;
+use crate::extract::parse_markdown_file;
+use crate::localize::localize_stream_file;
+use crate::models::{LocalizedShard, RepositoryConfiguration};
+use crate::timesheet::load_repository_config;
+
+fn load_all_shards(base_folder: &Path, tz: Tz) -> Result<Vec<LocalizedShard>, StreamdError> {
+    let config = RepositoryConfiguration::new();
+    let mut shards = Vec::new();
+
+    for entry in WalkDir::new(base_folder)
+        .max_depth(1)
+        .into_iter()
+        .filter_map(|e| e.ok())
+    {
+        let path = entry.path();
+        if path.extension().map(|e| e == "md").unwrap_or(false) {
+            let file_name = path.to_string_lossy().to_string();
+            let content = fs::read_to_string(path)?;
+            let stream_file = parse_markdown_file(&file_name, &content);
+
+            if let Ok(shard) = localize_stream_file(&stream_file, &config, tz) {
+                shards.push(shard);
+            }
+        }
+    }
+
+    Ok(shards)
+}
+
+pub fn run(date: Option<String>) -> Result<(), StreamdError> {
+    let settings = Settings::load()?;
+    let base_folder = Path::new(&settings.base_folder);
+
+    let repo_config = load_repository_config(base_folder)?;
+    let tz: Tz = repo_config
+        .timezone
+        .as_deref()
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(chrono_tz::UTC);
+
+    let target_date: NaiveDate = match date {
+        Some(s) => NaiveDate::parse_from_str(&s, "%Y%m%d").map_err(|_| {
+            StreamdError::ConfigError("Invalid date format, expected YYYYMMDD".into())
+        })?,
+        None => Utc::now().with_timezone(&tz).date_naive(),
+    };
+
+    let day_start = tz
+        .from_local_datetime(&NaiveDateTime::new(target_date, NaiveTime::MIN))
+        .earliest()
+        .unwrap()
+        .with_timezone(&Utc);
+    let day_end = tz
+        .from_local_datetime(&NaiveDateTime::new(
+            target_date + Days::new(1),
+            NaiveTime::MIN,
+        ))
+        .earliest()
+        .unwrap()
+        .with_timezone(&Utc);
+
+    let all_shards = load_all_shards(base_folder, tz)?;
+    let mut daily_shards: Vec<_> = all_shards
+        .into_iter()
+        .filter(|s| {
+            s.location
+                .get("file_type")
+                .map(|v| v == "daily")
+                .unwrap_or(false)
+        })
+        .filter(|s| s.moment >= day_start && s.moment < day_end)
+        .collect();
+    daily_shards.sort_by_key(|s| s.moment);
+
+    let editor = std::env::var("EDITOR").unwrap_or_else(|_| "vi".to_string());
+
+    if let Some(shard) = daily_shards.first() {
+        let file_path = shard.location.get("file").unwrap();
+        Command::new(&editor).arg(file_path).status()?;
+    } else {
+        let now_local = Utc::now().with_timezone(&tz);
+        let file_name = now_local.format("%Y%m%d-%H%M%S_daily.md").to_string();
+        let file_path = base_folder.join(&file_name);
+        fs::write(&file_path, "# ")?;
+        Command::new(&editor).arg(&file_path).status()?;
+        println!("Created {}", file_name);
+    }
+
+    Ok(())
+}

src/cli/commands/mod.rs

@@ -1,4 +1,5 @@
 pub mod completions;
+pub mod daily;
 pub mod edit;
 pub mod new;
 pub mod timesheet;