rule mask_self fails on Docker container

I'm trying to use dentist on a docker container, but the example always fails during the `mask_self` step. From my mac, I'm starting the container using `docker run -it --rm=true --platform linux/x86_64 centos:7 /bin/bash`. I'm then running the following:

```bash
yum update -y -q
yum install -y wget

wget https://github.com/conda-forge/miniforge/releases/latest/download/Mambaforge-Linux-x86_64.sh
sh Mambaforge-Linux-x86_64.sh -b -p /opt/mamba3
export PATH=/opt/mamba3/bin:$PATH
rm Mambaforge-Linux-x86_64.sh

mamba install -c conda-forge -c bioconda -y snakemake

wget https://github.com/a-ludi/dentist/releases/download/v3.0.0/dentist-example.tar.gz
tar -xzf dentist-example.tar.gz
cd dentist-example

snakemake --configfile=snakemake.yml --use-conda --cores=1
```

This causes the following error:

```
Error in rule mask_self:
jobid: 11
output: workdir/.reference.dentist-self.anno, workdir/.reference.dentist-self.data
log: logs/mask-self.reference.log (check log file(s) for error message)
conda-env: /dentist-example/.snakemake/conda/850bc5c09e81d3d6b875839f8fe0ed70
shell:
dentist mask --config=dentist.yml workdir/reference.dam workdir/reference.reference.las dentist-self 2> logs/mask-self.reference.log
(one of the commands exited with non-zero exit code; note that snakemake uses bash strict mode!)
```

The contents of `logs/mask-self.reference.log`:

```
{"executableVersion":"v3.0.0","refDb":"workdir/reference.dam","readsDb":"","dbAlignmentFile":"workdir/reference.reference.las","repeatMask":"dentist-self","configFile":"dentist.yml","debugRepeatMasks":false,"help":false,"maxCoverageReads":4294967295,"coverageBoundsReads":[0,0],"maxCoverageSelf":3,"coverageBoundsSelf":[0,3],"maxImproperCoverageReads":4294967295,"improperCoverageBoundsReads":[0,0],"properAlignmentAllowance":100,"quiet":false,"readCoverage":20,"revertOptionNames":[],"tracePointDistance":100,"verbosity":2}
{"thread":274939902976,"logLevel":"diagnostic","timestamp":637783965479794038,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.run","state":"enter"}
{"thread":274939902976,"logLevel":"diagnostic","timestamp":637783965479801084,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.readInputs","state":"enter"}
{"thread":274939902976,"logLevel":"diagnostic","state":"pre","command":["DBdump","workdir/reference.dam"],"timestamp":637783965479844193,"action":"execute","type":"pipe"}
{"thread":274939902976,"logLevel":"diagnostic","timestamp":637783965480006401,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.readInputs","state":"exit","timeElapsed":203652}
{"thread":274939902976,"logLevel":"diagnostic","timestamp":637783965480009609,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.run","state":"exit","timeElapsed":208842}
core.exception.AssertError@source/dentist/util/process.d(215): Attempting to fetch the front of an empty LinesPipe
----------------
??:? _d_assert_msg [0x40010b3e06]
??:? uint dentist.dazzler.numDbRecords(in immutable(char)[]) [0x4000dbef18]
??:? dentist.util.process.LinesPipe!(dentist.util.process.ProcessInfo, 0).LinesPipe dentist.dazzler.dbdump!(ulong[]).dbdump(in immutable(char)[], ulong[], in immutable(char)[][]) [0x4000dcbdad]
??:? uint[] dentist.dazzler.LocalAlignmentReader.contigLengths(immutable(char)[]) [0x4000dbfff3]
??:? dentist.dazzler.LocalAlignmentReader dentist.dazzler.LocalAlignmentReader.__ctor(const(immutable(char)[]), immutable(char)[], immutable(char)[], dentist.dazzler.BufferMode, dentist.common.alignments.base.TracePoint[]) [0x4000dbfc21]
??:? void dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.readInputs() [0x4000c73d52]
??:? void dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.run() [0x4000c73b09]
??:? dentist.commandline.ReturnCode dentist.commandline.runCommand!(2).runCommand(in immutable(char)[][]) [0x4000bbd656]
??:? dentist.commandline.ReturnCode dentist.commandline.run(in immutable(char)[][]) [0x4000b2850d]
??:? _Dmain [0x40009bee67]
```

Strangely, I can run the same series of commands on a CentOS 7 cluster with no issue. The contents of `logs/mask-self.reference.log` for the successful run are

```
{"executableVersion":"v3.0.0","refDb":"workdir/reference.dam","readsDb":"","dbAlignmentFile":"workdir/reference.reference.las","repeatMask":"dentist-self","configFile":"dentist.yml","debugRepeatMasks":false,"help":false,"maxCoverageReads":4294967295,"coverageBoundsReads":[0,0],"maxCoverageSelf":3,"coverageBoundsSelf":[0,3],"maxImproperCoverageReads":4294967295,"improperCoverageBoundsReads":[0,0],"properAlignmentAllowance":100,"quiet":false,"readCoverage":20,"revertOptionNames":[],"tracePointDistance":100,"verbosity":2}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913924743264,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.run","state":"enter"}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913924743707,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.readInputs","state":"enter"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","workdir/reference.dam"],"timestamp":637783913924766164,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","-h","workdir/reference.dam"],"timestamp":637783913924790405,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","workdir/reference.dam"],"timestamp":637783913924830211,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","-h","workdir/reference.dam"],"timestamp":637783913924851842,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913924889160,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.readInputs","state":"exit","timeElapsed":145216}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913924889516,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.assessRepeatStructure","state":"enter"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","workdir/reference.dam"],"timestamp":637783913924890069,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","-r","-h","workdir/reference.dam"],"timestamp":637783913924911577,"action":"execute","type":"pipe"}
{"alignmentType":"self","thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913925023014,"repetitiveRegions":null,"numRepetitiveRegions":185}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913925023427,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.assessRepeatStructure","state":"exit","timeElapsed":133711}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913925023646,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.writeRepeatMask","state":"enter"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","workdir/reference.dam"],"timestamp":637783913925025791,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","state":"pre","command":["DBdump","workdir/reference.dam"],"timestamp":637783913925047965,"action":"execute","type":"pipe"}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913925069691,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.writeRepeatMask","state":"exit","timeElapsed":45797}
{"thread":22377401060544,"logLevel":"diagnostic","timestamp":637783913925069958,"function":"dentist.commands.maskRepetitiveRegions.RepeatMaskAssessor.run","state":"exit","timeElapsed":326260}
```

I've also tried this on the `condaforge/mambaforge:4.11.0-0` container, but I get the same error.

Any insights are greatly appreciated!

The error occurs in dentist's mask_self rule when running inside a Docker container. The log shows an AssertError from dentist/util/process.d: 'Attempting to fetch the front of an empty LinesPipe'. Compare the failing log (only one DBdump call) with the successful log (multiple DBdump calls). Investigate the dentist command 'dentist mask' and its interaction with the dazzler DBdump tool. Check the container environment differences, possibly related to file paths, permissions, or the DBdump output. Start by examining the dentist source around source/dentist/util/process.d line 215 and the dbdump function.

Written by the indexing model from the issue text.