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Fix to build jets

Da Yu Tourequested to merge
dtou_fix_deltaphi into 2025-patches

Thanks to @tmombach, @jzhuo and @ahennequ for debugging this issue. We saw this in cuda-gdb:

(cuda-gdb) info cuda kernels
  Kernel Parent Dev Grid Status           SMs Mask   GridDim BlockDim Invocation                    
*      0      -   0 60177812 Active 0x0080000000000000 (928,1,1) (64,1,1) build_cone_jets::build_jets() 
(cuda-gdb) cuda thread 0    
CUDA focus unchanged.
(cuda-gdb) backtrace
#0  0x00007fdc734cce80 in build_cone_jets::build_jets
   <<<(928,1,1),(64,1,1)>>> ()
    at /group/hlt/hlt1/stack_RTA_2025_05_16_1/Allen/build.x86_64_v3-el9-gcc13+cuda12_4-opt+g/stack/Allen/device/jets/src/BuildConeJets.cu:20 in deltaPhi inlined from BuildConeJets.cu:200

which pointed to the while loops in deltaPhi that are stalling the kernels. fmod should be mathematically equivalent to what the while loop is trying to achieve.

FYI: @mfontana @decianm @thboettc @cagapopo @msaur @dovombru

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