fix: resolve clippy warnings and formatting issues for CI

- Fix doc_markdown warnings in WhatsApp channel
- Fix needless_pass_by_value in cron, health, migration, service modules
- Fix match_same_arms in migration.rs
- Fix too_many_lines in skills/mod.rs
- Fix manual_let_else in tools/file_write.rs
- Apply cargo fmt formatting fixes

All 435 tests pass, clippy clean.

src/service/mod.rs

@@ -6,7 +6,7 @@ use std::process::Command;
 
 const SERVICE_LABEL: &str = "com.zeroclaw.daemon";
 
-pub fn handle_command(command: super::ServiceCommands, config: &Config) -> Result<()> {
+pub fn handle_command(command: &super::ServiceCommands, config: &Config) -> Result<()> {
     match command {
         super::ServiceCommands::Install => install(config),
         super::ServiceCommands::Start => start(config),