Add spruce lines for B2HPi0 with Dalitz pi0 decays

This MR add two new lines for B^+ \to K^+ \pi^0 and B^+ \to \pi^+ \pi^0 decays with \pi^0 \to e^+ e^- \gamma, based on the experience of reconstructing D^+ \to \pi^+ \pi^0 decays in the Charm group. We've seen that the yield per inv fb increased by a factor of 10 between Run2 and Run3 for \pi^0 \to e^+ e^- \gamma decays, therefore it might now be worth including this final state for the B^+ \to h^+ \pi^0 decays. The yield will be small due to the low efficiency, but the sample would be softer than the calorimeter \pi^0 approach.

The lines has been run over all events in the sprucing testing snippet and the bandwidth is as follows:

Line	Eff	Rate
BuToKpPi0_Dalitz	2/371018 = 0.0000054	0.41 Hz
BuToPipPi0_Dalitz	3/371018 = 0.0000081	0.61 Hz

file_size = 171k

b/w (GB/s) = input rate (75.49 kHz for this HLT2 output file) x 0.171 (MB) / 371018

b/w (GB/s) = 0.000035 GB/s = 35 (KB/s)

Hlt/Hlt2Conf/python/Hlt2Conf/lines/bnoc/bTohh.py

@@ -14,9 +14,11 @@
 
 from GaudiKernel.SystemOfUnits import (
     MeV,  # will be needed once the full set of lines is back
+    picosecond,
 )
 
 from Hlt2Conf.lines.bnoc.builders import b_builder, basic_builder
+from Hlt2Conf.lines.bnoc.builders.basic_builder import make_dalitz_pi0s
 from Hlt2Conf.lines.bnoc.utils import check_process
 
 ##############################################
@@ -65,6 +67,69 @@ def make_BuToPipPi0(process):
     return line_alg
 
 
+@check_process
+def make_BuToKpPi0_Dalitz(process):
+    kaons = basic_builder.make_soft_kaons(
+        k_pidk_min=-0.5, p_min=2000 * MeV, pt_min=1000 * MeV, mipchi2_min=16
+    )
+    dalitz_pi0s = make_dalitz_pi0s(
+        p_min=2000 * MeV,
+        pt_min=1000 * MeV,
+        gamma_is_not_H=0.05,
+        gamma_is_photon=0.2,
+        min_ipchi2=16,
+    )
+
+    line_alg = b_builder.make_bbaryon_2body(
+        particles=[kaons, dalitz_pi0s],
+        descriptor="[B+ -> K+ pi0]cc",
+        mass_min=4700 * MeV,
+        mass_max=6200 * MeV,
+        pt_min=1500 * MeV,
+        pt_sum_min=2000 * MeV,
+        docachi2_max=25.0,
+        vchi2pdof_max=10.0,
+        ipchi2_max=25.0,
+        bpvfdchi2_min=25.0,
+        dira_min=0.999,
+        bpvltime_min=0.2 * picosecond,
+        bcvtx_sep_min=None,
+        daughter_index=1,
+    )
+    return line_alg
+
+
+@check_process
+def make_BuToPipPi0_Dalitz(process):
+    pips = basic_builder.make_soft_pions(
+        p_min=2000 * MeV, pt_min=1000 * MeV, mipchi2_min=16
+    )
+    dalitz_pi0s = make_dalitz_pi0s(
+        p_min=2000 * MeV,
+        pt_min=1000 * MeV,
+        gamma_is_not_H=0.05,
+        gamma_is_photon=0.2,
+        min_ipchi2=16,
+    )
+    line_alg = b_builder.make_bbaryon_2body(
+        particles=[pips, dalitz_pi0s],
+        descriptor="[B+ -> pi+ pi0]cc",
+        mass_min=4700 * MeV,
+        mass_max=6200 * MeV,
+        pt_min=1500 * MeV,
+        pt_sum_min=2000 * MeV,
+        docachi2_max=25.0,
+        vchi2pdof_max=10.0,
+        ipchi2_max=25.0,
+        bpvfdchi2_min=25.0,
+        dira_min=0.999,
+        bpvltime_min=0.2 * picosecond,
+        bcvtx_sep_min=None,
+        daughter_index=1,
+    )
+    return line_alg
+
+
 @check_process
 def make_BuToL0barPp_LL(process):
     if process == "spruce":