v0.2.4

• PSLF .epc: read support for GE PSLF power flow cases, including .epc
  extension inference and pslf / epc input aliases. The reader is read only
  and keeps source text plus warnings for sections outside Network.
• PowerWorld .pwb: expanded binary reader coverage across older and newer
  header constants, with stricter record probes, companion format parity checks,
  and clearer rejection of unsupported vintages.
• PowerWorld .pwd: display parsing keeps the separate display API path and
  retains the malformed input invariant: corrupt or truncated display files
  return a structured error or a parsed display, not a panic.
• No C ABI break; PIO_ABI_VERSION stays 3.

What's Changed

• Add PSLF EPC reader + Improve coverage of PW vintages by @samtalki in #125
• release: v0.2.4 by @samtalki in #127

Full Changelog: v0.2.3...v0.2.4