feat(task): dependencies (#26467)

This commit adds support for "dependencies" in `deno task` subcommand:
```jsonc
{
    "tasks": {
        "build": "deno run -RW build.ts",
        "generate": "deno run -RW generate.ts",
        "serve": {
            "command": "deno run -RN server.ts",
            "dependencies": ["build", "generate"]
        }
    }
}
```
Executing `deno task serve` will first execute `build` and `generate`
tasks (in parallel) and once both complete the `serve` task will be executed.

Number of tasks run in parallel is equal to the no of cores on the
machine, and respects `DENO_JOBS` env var if one is specified.

Part of https://github.com/denoland/deno/issues/26462

---------

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Co-authored-by: Marvin Hagemeister <marvin@deno.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/cli/schemas/config-file.v1.json b/cli/schemas/config-file.v1.json
index 56a8090f9..3ba803ef8 100644
--- a/cli/schemas/config-file.v1.json
+++ b/cli/schemas/config-file.v1.json
@@ -448,6 +448,13 @@
                   "type": "string",
                   "required": true,
                   "description": "The task to execute"
+                },
+                "dependencies": {
+                  "type": "array",
+                  "items": {
+                    "type": "string"
+                  },
+                  "description": "Tasks that should be executed before this task"
                 }
               }
             }