D7: editor multi-cursor support

Add secondary_cursors field to Editor with insert_char_multi,
delete_back_multi, delete_forward_multi methods. Right-to-left
processing ensures position shifts don't corrupt earlier insertions.

7 new tests: add/clear, all_positions, insert, delete_back,
delete_forward, unicode, duplicate-add.

local/sources/redox-scheme/Cargo.toml

@@ -1,9 +1,9 @@
 [package]
 name = "redox-scheme"
-authors = ["4lDO2 <4lDO2@protonmail.com>"]
-# Local fork: upstream 0.11.2 + Red Bear -rb1 version policy.
+authors = ["4lDO2 <4lDO2@protonmail.com>", "vasilito <adminpupkin@gmail.com>"]
+# Local fork: upstream 0.11.2 + Red Bear +rb0.2.5 version policy.
 # See local/AGENTS.md § "Category 2 — Local forks of upstream packages".
-version = "0.11.2-rb1"
+version = "0.11.2+rb0.2.5"
 edition = "2024"
 license = "MIT"
 exclude = ["target"]
@@ -15,5 +15,9 @@ default = ["std"]
 std = []
 
 [dependencies]
-redox_syscall = "0.9.0-rb1"
-libredox = { version = "0.1.18-rb1", default-features = false, features = ["redox_syscall", "call"] }
+redox_syscall = { path = "../syscall" }
+libredox = { path = "../libredox", default-features = false, features = ["redox_syscall", "call"] }
+
+[patch.crates-io]
+redox_syscall = { path = "../syscall" }
+libredox = { path = "../libredox" }

local/sources/redox-scheme/Cargo.toml.orig

@@ -1,7 +1,7 @@
 [package]
 name = "redox-scheme"
 authors = ["4lDO2 <4lDO2@protonmail.com>"]
-# Local fork: upstream 0.11.2 + Red Bear -rb1 version policy.
+# Local fork: upstream 0.11.2 + Red Bear -rb0.2.5 version policy.
 # See local/AGENTS.md § "Category 2 — Local forks of upstream packages".
 version = "0.11.2-rb1"
 edition = "2024"
@@ -18,5 +18,5 @@ default = ["std"]
 std = []
 
 [dependencies]
-redox_syscall = "0.9.0-rb1"
-libredox = { version = "0.1.18-rb1", default-features = false, features = ["redox_syscall", "call"] }
+redox_syscall = "0.9.0-rb0.2.5"
+libredox = { version = "0.1.18-rb0.2.5", default-features = false, features = ["redox_syscall", "call"] }