comparator doesn't work when repo contains filenames starting with numbers

[mo271]

While lake etc supports having filename/modules start with numbers, it seems that comparator doens't.

Te recreate the bug, clone https://github.com/mo271/FilesStartingWithNumbers and run

~/FilesStartingWithNumbers (main)> lake env ~/comparator/.lake/build/bin/comparator config_with_problematic_names.json 
Building FilesStartingWithNumbers.«1»
⣾ [0/0] Running job computationPANIC at Lean.modToFilePath.go Lean.Util.Path:46:20: ill-formed import
backtrace:
/home/firsching/.elan/toolchains/leanprover--lean4---v4.27.0/bin/../lib/lean/libleanshared.so(+0x9b23bfe) [0x7f62fe923bfe]
[...rest of stacktrace...]

When changing the escape := false in ./Main.lean to escape := true (suggested by Eric Wieser) one gets a different error:

lake env ~/comparator/.lake/build/bin/comparator config_with_problematic_names.json
Building FilesStartingWithNumbers.«1»
⚠ [2/2] Replayed FilesStartingWithNumbers.«1»
warning: FilesStartingWithNumbers/1.lean:1:8: declaration uses 'sorry'
Build completed successfully (2 jobs).
Exporting #[foo, propext, Quot.sound, Classical.choice, Nat.add, Nat.sub, Nat.mul, Nat.pow, Nat.gcd, Nat.div, Nat.mod, Nat.beq, Nat.ble, Nat.land, Nat.lor, Nat.xor, Nat.shiftLeft, Nat.shiftRight, String.ofList] from FilesStartingWithNumbers.«1»
uncaught exception: process 'landrun' exited with code 134
stderr:
PANIC at Lean.modToFilePath.go Lean.Util.Path:46:20: ill-formed import
backtrace:
lean4export(+0x9ba2f9e) [0x55a336c9cf9e]
[rest of the 

but with a further fix to lean4export it seems to work, see leanprover/lean4export#19