game_data: PilotRoster loader — player squadron flight assignments

Decode the UNITS/ZUNITS player-unit tables (GP_HANGAR_ARSENAL.pak) into
flight assignments: which pilot flies each callsign (Rhino1→Katana,
Bird1→Sandra, …), plus the player craft. Assignments are `Callsign<N>-
Pilot` tokens, extracted by shape.

138 configs; the distinct line-ups trace the campaign's story — Raymond
leads Rhino flight early (Rhino1=Raymond, Rhino2=Katana), then Katana
takes the lead (Rhino1=Katana, Rhino2=Ellen, Rhino3=Gene, Rhino4=Yoji).
Example `flights` prints the line-ups. +1 test.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

crates/sylpheed-formats/examples/flights.rs

@@ -0,0 +1,17 @@
+use sylpheed_formats::{game_data as gd, PakArchive};
+fn main(){
+    let disc=std::env::var("SYLPHEED_DISC").unwrap();
+    let pak=PakArchive::open(format!("{disc}/dat/GP_HANGAR_ARSENAL.pak")).unwrap();
+    let rosters=gd::load_pilot_rosters(&pak);
+    // distinct rosters by their pilot set
+    let mut seen=std::collections::BTreeSet::new(); let mut shown=0;
+    println!("{} pilot-roster configs; distinct line-ups:", rosters.len());
+    for r in &rosters{
+        let key:String=r.pilots.iter().map(|(c,p)|format!("{c}:{p}")).collect::<Vec<_>>().join(",");
+        if seen.insert(key) && shown<8 {
+            shown+=1;
+            let flt:Vec<String>=r.pilots.iter().map(|(c,p)|format!("{c}={p}")).collect();
+            println!("  {}", flt.join("  "));
+        }
+    }
+}