Enhancements to date/time functions: The "weekday -N" modifier moves

the date backward in time.  The "end of day/month/year" modifiers added.

FossilOrigin-Name: 88901fffcd445ccb97e4e379ea15d8b06d87b8170cad0f717c909944ff21851f

diff --cc manifest
index 5f8e19c14059cef13bf3f4dcbfdea17bd82ebef6,f62a70b423b9d2888e8248782fdb592c544c7598..c12e4ac06832393002ca4bfa6fd27e3dd55f803b
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Add\snew\sassert()s\sto\shelp\sstatic\sanalyzers\srealize\sthat\sthe\scode\sis\scorrect.
- D 2026-06-29T15:11:58.186
 -C Add\s"end\sof\sday/month/year"\smodifiers\sto\sdate/time\sfunctions.
 -D 2026-07-01T11:57:20.103
++C Enhancements\sto\sdate/time\sfunctions:\s\sThe\s"weekday\s-N"\smodifier\smoves\nthe\sdate\sbackward\sin\stime.\s\sThe\s"end\sof\sday/month/year"\smodifiers\sadded.
++D 2026-07-01T12:11:41.802
  F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
  F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
  F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@@ -2210,8 -2210,8 +2210,9 @@@ F tool/warnings-clang.sh bbf6a1e685e534
  F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
  F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
  F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
- P 3e80958a7052a123f4599d64baa8cc31a761e5a58d04c75ca38f2a375d247808
- R 6e225e2a5b21c61670a4cf3bac94cdef
 -P e31bea6ce188fb3ae2d8da132a40a182431d701dc6b991af470337a1cdd3f8e4
++P 007f0496619e571092382a3668b6bbcc17919908895dc4be71f8d1b6ec2aeeed 2c4cb3223c6c56d05fe91b8d19b60eac26a274e41f34a2d8f2cf911927581932
+ R 1e8cc3c2fef8cd515a643be551bc5111
++T +closed 2c4cb3223c6c56d05fe91b8d19b60eac26a274e41f34a2d8f2cf911927581932
  U drh
- Z 2f447aaf8cc29ef8d2182c61654b2dfa
 -Z 2e9ade7347393c5621e35f8d1718f262
++Z 72253f088d1bca64ce0c9a09dc87f11f
  # Remove this line to create a well-formed Fossil manifest.

diff --cc manifest.uuid
index a755ac632e1ee4e46548cb4e888934aaf3c5d0df,3ff30545bb6560c84b94ffa44db239e26c670740..d50e37fef0257917e566e919529f3e5bbd7c68cd
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- 007f0496619e571092382a3668b6bbcc17919908895dc4be71f8d1b6ec2aeeed
 -2c4cb3223c6c56d05fe91b8d19b60eac26a274e41f34a2d8f2cf911927581932
++88901fffcd445ccb97e4e379ea15d8b06d87b8170cad0f717c909944ff21851f