fix: resolve 11 P1 bugs from audit (leaderboard, SQL, coop, jump, lifecycle, schematics, config)

- leaderboard: parse M:SS.mmm/H:MM:SS(.mmm), switch TIME sort to long (п.25)
- sql: single Hikari pool, non-blocking connect, adaptive init order, settings JSON round-trip (п.27-30)
- coop: remove unregister recursion via session-only leave + reentrancy guard (п.24)
- jump: perpendicular jitter for diagonal heading, valid safety-fallback on retry exhaustion (п.32-33)
- lifecycle: fall threshold relative to course, lead via generated-blocks counter, one-time rewards once (п.35-37)
- schematics: catch RuntimeExceptions, validate size, 10MB file limit (п.31)
- config merge: preserve block-sequence lists and ignored sections, fix path reversal (п.26)
- tests: +31 (score, jump, schematics, config merge) = 72 total

config/checkstyle/suppressions.xml

@@ -35,6 +35,13 @@
     <suppress checks="IllegalCatch" files=".*[\\/]command[\\/]core[\\/]LoParkourCommand\.java"/>
     <suppress checks="IllegalCatch" files=".*[\\/]config[\\/]core[\\/]merge[\\/]ConfigUpdater\.java"/>
 
+    <!--
+      SchematicManager: catches RuntimeException so a corrupted/truncated schematic
+      (WorldEdit/Bukkit throw unchecked exceptions) is skipped instead of breaking
+      plugin enable. Not swallowing — the failure is logged at SEVERE with the cause.
+    -->
+    <suppress checks="IllegalCatch" files=".*[\\/]schematic[\\/]core[\\/]SchematicManager\.java"/>
+
     <!-- ===== IllegalCatch / NPathComplexity / WhitespaceAround (legacy debt) ===== -->
     <suppress checks="IllegalCatch" files=".*[\\/]LoParkour.java"/>
     <suppress checks="NPathComplexity" files=".*[\\/]adaptive[\\/]bootstrap[\\/]AdaptiveServices.java"/>