add submodule on tree-sitter-rebase, add to languages

.gitmodules

@@ -178,3 +178,7 @@
 	path = helix-syntax/languages/tree-sitter-git-diff
 	url = https://github.com/the-mikedavis/tree-sitter-git-diff.git
 	shallow = true
+[submodule "helix-syntax/languages/tree-sitter-rebase"]
+	path = helix-syntax/languages/tree-sitter-rebase
+	url = https://github.com/the-mikedavis/tree-sitter-rebase.git
+	shallow = true

book/src/generated/lang-support.md

@@ -35,6 +35,7 @@
 | protobuf | ✓ |  | ✓ |  |
 | python | ✓ | ✓ | ✓ | `pylsp` |
 | racket |  |  |  | `racket` |
+| rebase | ✓ |  |  |  |
 | ruby | ✓ |  | ✓ | `solargraph` |
 | rust | ✓ | ✓ | ✓ | `rust-analyzer` |
 | scala | ✓ |  | ✓ | `metals` |

helix-syntax/languages/tree-sitter-rebase

@@ -0,0 +1 @@
+Subproject commit 4b572504d80832c3271dc1c9b351c756dbe75d37

languages.toml

@@ -490,3 +490,12 @@ file-types = ["diff"]
 injection-regex = "diff"
 comment-token = "#"
 indent = { tab-width = 2, unit = "  " }
+
+[[language]]
+name = "rebase"
+scope = "git.rebase"
+roots = []
+file-types = ["git-rebase-todo"]
+injection-regex = "rebase"
+comment-token = "#"
+indent = { tab-width = 2, unit = " " }