@OP. Could you please clarify on alleles and quality?
UTR3 Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 82411 82411 G T hom 84.5 60 0 4
UTR3 Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 82437 82437 A C hom 87.5 60 0 4
For these two lines, expected resultant alleles are G/T-A/C. Is it G/T-A/C or G/A-T/C?
If the alleles are G/T-A/C (as in OP):
$ awk -v OFS="\t" '{print $1,$2,$3,$4,$5,$6"/"$7,$8,$11,$12}' test.txt | datamash -g1 unique 2 unique 3 collapse 4-9 | awk -v OFS="\t" '{gsub(",","-");gsub("-",",",$2)}1'
AnnoPos gene chr pos1 pos2 ref/alt genotype ref-depth alt-depth
UTR3 Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 82411-82437 82411-82437 G/T-A/C hom-hom 0-0 4-4
exonic Eucgr.A00214.1.v2.0,Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 84195-84209-84631 84195-84209-84631 C/T-G/C-C/T hom-hom-het 0-0-5 17-17-7
intronic Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 84718-84754-89492 84718-84754-89492 C/T-C/T-C/T het-het-het 7-7-2 5-5-4
ps: screenshot in calc is attached here.

If the alleles are G/A-T/C, try this:
$ datamash -g1 unique 2 unique 3 collapse 4-8,11,12 < test.txt | awk -v OFS="\t" '{gsub(",","-"); gsub("-","/",$6); gsub("-","/",$7);gsub("-",",",$2); print $1,$2,$3,$4,$5,$6"-"$7,$8,$9,$10}'
AnnoPos gene chr pos1 pos2 ref-alt genotype ref-depth alt-depth
UTR3 Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 82411-82437 82411-82437 G/A-T/C hom-hom 0-0 4-4
exonic Eucgr.A00214.1.v2.0,Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 84195-84209-84631 84195-84209-84631 C/G/C-T/C/T hom-hom-het 0-0-5 17-17-7
intronic Eucgr.A00214.1.v2.0,Eucgr.A00214.2.v2.0 Chr01 84718-84754-89492 84718-84754-89492 C/C/C-T/T/T het-het-het 7-7-2 5-5-4
ps: Display is not optimal. Took a screenshot of the tsv in calc.

ps2: Datamash is available in most of the linux repos, conda channels and home brew linux