Omit empty uv.tool.dev-dependencies on uv init (#5406)

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## Summary

Implements #5340

## Test Plan

<!-- How was it tested? -->

crates/uv/src/commands/project/init.rs

@@ -173,9 +173,6 @@ pub(crate) async fn init(
         description = "Add your description here"{readme}
         requires-python = "{requires_python}"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "#,
         readme = if no_readme { "" } else { "\nreadme = \"README.md\"" },
         requires_python = requires_python.specifiers(),

crates/uv/tests/init.rs

@@ -39,9 +39,6 @@ fn init() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -100,9 +97,6 @@ fn init_no_readme() -> Result<()> {
         description = "Add your description here"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -143,9 +137,6 @@ fn init_current_dir() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -209,9 +200,6 @@ fn init_dot_args() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -288,9 +276,6 @@ fn init_workspace() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -383,9 +368,6 @@ fn init_workspace_relative_sub_package() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -479,9 +461,6 @@ fn init_workspace_outside() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -560,9 +539,6 @@ fn init_invalid_names() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -695,9 +671,6 @@ fn init_nested_workspace() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.12"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -927,9 +900,6 @@ fn init_requires_python_workspace() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.10"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -980,9 +950,6 @@ fn init_requires_python_version() -> Result<()> {
         readme = "README.md"
         requires-python = ">=3.8"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });
@@ -1034,9 +1001,6 @@ fn init_requires_python_specifiers() -> Result<()> {
         readme = "README.md"
         requires-python = "==3.8.*"
         dependencies = []
-
-        [tool.uv]
-        dev-dependencies = []
         "###
         );
     });