Replace the former dynamic-continuation prompt logic with backslash-escape

prompt expansion, include some expansions that serve the same role as the
old dynamic-continuation prompts.  This allows greater user
configurability.

FossilOrigin-Name: 052631202e4dd930d93434b7003e73b23557934421ace5d2f382f041638d5518

diff --cc manifest
index 96d0083569ce4a2e4667e189ade34ee2b71770c7,552e3e4a410eb1bdc0ffd8077434b047cb458c22..02d304d6122146fd6b54ea14dde65e468f204b53
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Clean-ups\sin\sprompt\sgeneration\sin\sthe\sCLI.
- D 2026-04-09T18:51:09.198
 -C Add\sthe\s\B\sescape\sfor\sCLI\sprompts.\s\sChange\sthe\sdefault\sprompts\sto\nuse\s\f,\s\H,\sand\s\B.
 -D 2026-04-10T20:06:34.810
++C Replace\sthe\sformer\sdynamic-continuation\sprompt\slogic\swith\sbackslash-escape\nprompt\sexpansion,\sinclude\ssome\sexpansions\sthat\sserve\sthe\ssame\srole\sas\sthe\nold\sdynamic-continuation\sprompts.\s\sThis\sallows\sgreater\suser\nconfigurability.
++D 2026-04-10T20:14:16.225
  F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
  F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
  F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@@ -2197,8 -2197,8 +2197,9 @@@ F tool/warnings-clang.sh bbf6a1e685e534
  F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
  F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
  F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
- P 8fd48b9fe47d47b3eca31d187f1d98174c257daea220ae7be18e4c82764d9d5c
- R 7ffb65d89e42eb90bf23dccbc7a1df3f
 -P 6aafb76c74b73aafef74250dae9c8cbe73226c0efb606e8f80ea761b3293cf9d
++P e2c9d4c6b731ea9afbb9cb22f86a3db3670ca67968f15891dc46ae1fc9ba34dc 354325b6f396bda38bbb82e7d38aa50d3d6441e1ebb9b578aed8e0bcf62f9911
+ R 10023fb5872b0939880b2eb9aec2ef11
++T +closed 354325b6f396bda38bbb82e7d38aa50d3d6441e1ebb9b578aed8e0bcf62f9911
  U drh
- Z ee302bdc160a37743cf8ada2bf8fc7e4
 -Z c3b3ebd71cd1378ad565509dcb2c7b21
++Z 0caf1772228f87bb1b8b817e19db97e9
  # Remove this line to create a well-formed Fossil manifest.

diff --cc manifest.uuid
index 8a875c645a61fb0ee327e5c2e3778b31a3210efc,2c3268c216f75b89b7e80e905da86239e33dc0be..80d801332e986710b4e1095cd6ee2cb94e56ff44
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- e2c9d4c6b731ea9afbb9cb22f86a3db3670ca67968f15891dc46ae1fc9ba34dc
 -354325b6f396bda38bbb82e7d38aa50d3d6441e1ebb9b578aed8e0bcf62f9911
++052631202e4dd930d93434b7003e73b23557934421ace5d2f382f041638d5518