refactor: split long RSS parser functions for maintainability

.github/copilot-instructions.md

@@ -0,0 +1,128 @@
+# feedparser-rs Copilot Instructions
+
+## Project Overview
+High-performance RSS/Atom/JSON Feed parser in Rust with Python (PyO3) and Node.js (napi-rs) bindings. Drop-in replacement for Python's `feedparser` with 10-100x performance improvement.
+
+**MSRV:** Rust 1.88.0 | **Edition:** 2024 | **License:** MIT/Apache-2.0
+
+## Architecture
+
+### Workspace Structure
+- **`crates/feedparser-rs-core`** — Pure Rust parser. All parsing logic lives here.
+- **`crates/feedparser-rs-py`** — Python bindings via PyO3/maturin.
+- **`crates/feedparser-rs-node`** — Node.js bindings via napi-rs.
+
+### Parser Flow
+1. `parse()` → `detect_format()` identifies RSS/Atom/JSON
+2. Routes to `parser/rss.rs`, `parser/atom.rs`, or `parser/json.rs`
+3. Namespace handlers in `namespace/` extract iTunes, Dublin Core, Media RSS, Podcast 2.0
+4. Returns `ParsedFeed` with `bozo` flag for error tolerance
+
+## Idiomatic Rust & Performance
+
+### Type Safety First
+- Prefer strong types over primitives: `FeedVersion` enum, not `&str`
+- Use `Option<T>` and `Result<T, E>` — never sentinel values
+- Leverage generics and trait bounds for reusable code:
+```rust
+fn collect_limited<T, I: Iterator<Item = T>>(iter: I, limit: usize) -> Vec<T> {
+    iter.take(limit).collect()
+}
+```
+
+### Zero-Cost Abstractions
+- Use `&str` over `String` in function parameters
+- Prefer iterators over index-based loops: `.iter().filter().map()`
+- Use `Cow<'_, str>` when ownership is conditionally needed
+- Avoid allocations in hot paths — reuse buffers where possible
+
+### Edition 2024 Features
+- Use `gen` blocks for custom iterators where applicable
+- Leverage improved async patterns for HTTP module
+- Apply new lifetime elision rules for cleaner signatures
+
+### Safety Guidelines
+- `#![warn(unsafe_code)]` is enabled — avoid `unsafe` unless absolutely necessary
+- All public APIs must have doc comments (`#![warn(missing_docs)]`)
+- Use `thiserror` for error types with proper `#[error]` attributes
+
+## Critical Conventions
+
+### Error Handling: Bozo Pattern (MANDATORY)
+**Never panic or return errors for malformed input.** Set `bozo = true` and continue:
+```rust
+match parse_date(&text) {
+    Some(dt) => entry.published = Some(dt),
+    None => {
+        feed.bozo = true;
+        feed.bozo_exception = Some(format!("Invalid date: {text}"));
+        // Continue parsing!
+    }
+}
+```
+
+### API Compatibility with Python feedparser
+Field names must match `feedparser` exactly: `feed.title`, `entries[0].summary`, `version` returns `"rss20"`, `"atom10"`
+
+### XML Parsing with quick-xml
+Use tolerant mode — no strict validation:
+```rust
+let mut reader = Reader::from_reader(data);
+reader.config_mut().trim_text(true);
+// Do NOT enable check_end_names — tolerance over strictness
+```
+
+## Development Commands
+
+All automation via `cargo-make`:
+
+| Command | Purpose |
+|---------|---------|
+| `cargo make fmt` | Format with nightly rustfmt |
+| `cargo make clippy` | Lint (excludes py bindings) |
+| `cargo make test-rust` | Rust tests (nextest) |
+| `cargo make pre-commit` | fmt + clippy + test-rust |
+| `cargo make bench` | Criterion benchmarks |
+| `cargo make msrv-check` | Verify MSRV 1.88.0 compatibility |
+
+### Bindings
+```bash
+# Python
+cd crates/feedparser-rs-py && maturin develop && pytest tests/ -v
+
+# Node.js
+cd crates/feedparser-rs-node && pnpm install && pnpm build && pnpm test
+```
+
+## Testing Patterns
+
+Use `include_str!()` for fixtures in `tests/fixtures/`:
+```rust
+#[test]
+fn test_rss20_basic() {
+    let xml = include_str!("../../tests/fixtures/rss/example.xml");
+    let feed = parse(xml.as_bytes()).unwrap();
+    assert!(!feed.bozo);
+}
+```
+
+Always verify malformed feeds set bozo but still parse:
+```rust
+#[test]
+fn test_malformed_sets_bozo() {
+    let xml = b"<rss><channel><title>Broken</title></rss>";
+    let feed = parse(xml).unwrap();
+    assert!(feed.bozo);
+    assert_eq!(feed.feed.title.as_deref(), Some("Broken")); // Still parsed!
+}
+```
+
+## Commit & Branch Conventions
+- Branch: `feat/`, `fix/`, `docs/`, `refactor/`, `test/`
+- Commits: [Conventional Commits](https://conventionalcommits.org/)
+
+## What NOT to Do
+- Don't use `.unwrap()` or `.expect()` in parser code — use bozo pattern
+- Don't add dependencies without workspace-level declaration in root `Cargo.toml`
+- Don't skip `--exclude feedparser-rs-py` in workspace-wide Rust commands (PyO3 needs special handling)
+- Don't break API compatibility with Python feedparser field names