refactor: deduplicate filter plugins, extract helpers across codebase

Bug fixes:
- client: add error field to ApiResponse to avoid swallowing server errors
- args/config: fix list_format default mismatch (5 vs 7 columns)
- client: url-encode size param in set_item_size

Dedup - filter plugins:
- Extract count_option() and pattern_option() helpers, replace 7 identical options()
- Add #[derive(Clone)] to all filter structs; remove verbose clone_box() impls
- Simplify FilterChain clone() and impl Clone for Box<dyn FilterPlugin>
- Add filter_clone_box! macro for future use
- Fix doctest example missing clone_box

Dedup - server API:
- Extract spawn_body_reader() with LimitBehavior enum for body streaming
- Extract check_binary_content() helper
- Extract stream_with_offset_and_length() helper
- Extract generate_status() helper in status.rs
- Extract append_query_params() helper in client.rs

Dedup - other:
- Extract yaml_value_to_string() in meta_plugin/mod.rs
- Extract item_from_row() in db.rs
- Delete unused DisplayListItem struct

Misc:
- Remove duplicate doc comment in compression_service.rs

src/args.rs

@@ -228,7 +228,7 @@ pub struct OptionsArgs {
     #[arg(
         long,
         env("KEEP_LIST_FORMAT"),
-        default_value("id,time,size,tags,meta:hostname")
+        default_value("id,time,size,meta:text_line_count,tags,meta:hostname_short,meta:command")
     )]
     #[arg(help("A comma separated list of columns to display with --list"))]
     pub list_format: String,