Fix false-negatives in the sqlite3ExprCanReturnSubtype() routine having

to do with CASE, CAST, and COLLATE expressions and the "+" no-op operator.
[forum:/forumpost/1f0168a120:Forum post 1f0168a120].

FossilOrigin-Name: 9be94e961457967408cbd0acf11877fbb323a48eee405fff53755770f1b3261a

diff --cc manifest
index fabe043bd62453d4ea4c22bb792225fb5dd77bba,8aa80937932485dd94cfd1141e01d86311b5a236..6c4cdeeffa7aa9375d4c38c52520317379661071
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Have\swindow\sfunctions\ssum(),\stotal()\sand\savg()\scorrectly\shandle\sthe\sobscure\scase\swhere\sinteger\soverflow\soccurs\sas\spart\sof\sthe\ssame\sstep\sthat\sadds\sthe\sfirst\sreal\svalue\sto\sthe\srunning\stotal.
- D 2026-05-15T18:36:11.222
 -C Improved\scomment\son\ssqlite3ExprCanReturnSubtype()\sas\swell\sas\sone\svery\nminor\sefficiency\simprovement.
 -D 2026-05-16T16:02:08.141
++C Fix\sfalse-negatives\sin\sthe\ssqlite3ExprCanReturnSubtype()\sroutine\shaving\nto\sdo\swith\sCASE,\sCAST,\sand\sCOLLATE\sexpressions\sand\sthe\s"+"\sno-op\soperator.\n[forum:/forumpost/1f0168a120:Forum\spost\s1f0168a120].
++D 2026-05-16T17:28:56.739
  F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
  F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
  F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@@ -2205,8 -2205,8 +2205,9 @@@ F tool/warnings-clang.sh bbf6a1e685e534
  F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
  F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
  F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
- P 350152d5124b71b3dd640c109dbac5f05a3a9583a335fbe25f707e1b754c1c74
- R c50b0f6f28baeeeed7b287faad56d833
- U dan
- Z 51fc95b4ddd107a4261fc9ca2af10aec
 -P 69c9a82cbaea7b6faa6a357dd884b1e0d2bc684d847efb31a2d64c75fabf5428
++P 614f8cbc374c7a2d39826706f16ab1c17e75abb420a70be356c7eefa95b271a5 b57d6b76b0f9f4f154997af83f14d545bf2b6b8f7194746835e4c34885db227a
+ R 2a2f348cdea2758e17a1878550fc52a0
++T +closed b57d6b76b0f9f4f154997af83f14d545bf2b6b8f7194746835e4c34885db227a
+ U drh
 -Z e0cf26d7b2dbc3e008636c0b83266f18
++Z 553bd5602d0d8a7a6c58fe9827c438c2
  # Remove this line to create a well-formed Fossil manifest.

diff --cc manifest.uuid
index 3a231e28e5d60fcf6731babcdfefebea910d4864,3de14ecf50413e01ddc4055897caba1e83d4171b..7d64f9b5357db6649e9bd2f8b9c865004a10e108
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- 614f8cbc374c7a2d39826706f16ab1c17e75abb420a70be356c7eefa95b271a5
 -b57d6b76b0f9f4f154997af83f14d545bf2b6b8f7194746835e4c34885db227a
++9be94e961457967408cbd0acf11877fbb323a48eee405fff53755770f1b3261a