Get last commit parent tracking

[zeripath]

This PR is an alternative to #15891.

In this we do some basic parent tracking and if we discover that a path has a sha change when there is a single mainline we can declare that path found.

Further if we reach a point whereby the number of files is less than 70 we will ask git to track these in rev-list as it appears that git is fast enough at that point.

[zeripath]

Closing in favour of #16059 which is faster

[zeripath]

Reopening as this appears better tolerated by codeberg.

[codecov-commenter]

Codecov Report

Merging #16042 (4c851b1) into main (ee5e1c4) will increase coverage by 0.10%.
The diff coverage is 60.38%.

@@            Coverage Diff             @@
##             main   #16042      +/-   ##
==========================================
+ Coverage   44.06%   44.17%   +0.10%     
==========================================
  Files         683      683              
  Lines       82358    82518     +160     
==========================================
+ Hits        36295    36455     +160     
+ Misses      40176    40138      -38     
- Partials     5887     5925      +38     

Impacted Files	Coverage Δ
modules/git/pipeline/lfs_nogogit.go	0.00% <0.00%> (ø)
modules/indexer/code/bleve.go	68.22% <0.00%> (-0.59%)	⬇️
modules/indexer/code/elastic_search.go	1.64% <0.00%> (-0.02%)	⬇️
modules/git/repo_language_stats_nogogit.go	43.90% <33.33%> (-0.68%)	⬇️
modules/git/batch_reader.go	50.42% <50.61%> (-3.33%)	⬇️
modules/git/commit_info_nogogit.go	68.21% <72.17%> (+0.11%)	⬆️
modules/indexer/stats/db.go	42.85% <0.00%> (-7.15%)	⬇️
modules/queue/queue_channel.go	91.66% <0.00%> (-5.00%)	⬇️
modules/git/repo_base_nogogit.go	82.85% <0.00%> (-2.86%)	⬇️
modules/git/utils.go	62.50% <0.00%> (-2.78%)	⬇️
... and 16 more

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