fix: add [project.scripts] to crewai package for uv tool install (#6010)

The crewai package did not declare any [project.scripts] entry point,
causing `uv tool install crewai` to fail with:

    No executables are provided by package `crewai`; removing tool
    error: Failed to install entrypoints for `crewai`

The CLI entry point was only defined in the crewai-cli sub-package.
Add `crewai = "crewai_cli.cli:crewai"` to lib/crewai/pyproject.toml
so that installing the main package also exposes the executable.

Add regression tests verifying the entry point is declared, importable,
and consistent between both packages.

Co-Authored-By: João <joao@crewai.com>

lib/cli/tests/test_entrypoint_consistency.py

@@ -0,0 +1,55 @@
+"""Tests ensuring the crewai and crewai-cli packages expose consistent entry points.
+
+Regression test for https://github.com/crewAIInc/crewAI/issues/6010:
+`uv tool install crewai` failed because only crewai-cli declared [project.scripts].
+Both packages must declare the same entry point so that installing either one
+via `uv tool install` exposes the `crewai` executable.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+import tomllib
+
+
+LIB_DIR = Path(__file__).resolve().parents[2]
+CREWAI_PYPROJECT = LIB_DIR / "crewai" / "pyproject.toml"
+CLI_PYPROJECT = LIB_DIR / "cli" / "pyproject.toml"
+
+
+@pytest.fixture
+def crewai_scripts() -> dict[str, str]:
+    data = tomllib.loads(CREWAI_PYPROJECT.read_text())
+    return data.get("project", {}).get("scripts", {})
+
+
+@pytest.fixture
+def cli_scripts() -> dict[str, str]:
+    data = tomllib.loads(CLI_PYPROJECT.read_text())
+    return data.get("project", {}).get("scripts", {})
+
+
+def test_crewai_package_has_crewai_script(crewai_scripts: dict[str, str]) -> None:
+    """The crewai package must declare a 'crewai' script entry point."""
+    assert "crewai" in crewai_scripts, (
+        "lib/crewai/pyproject.toml must have [project.scripts] crewai = ... "
+        "so that `uv tool install crewai` exposes the crewai executable."
+    )
+
+
+def test_cli_package_has_crewai_script(cli_scripts: dict[str, str]) -> None:
+    """The crewai-cli package must declare a 'crewai' script entry point."""
+    assert "crewai" in cli_scripts
+
+
+def test_entrypoint_targets_same_function(
+    crewai_scripts: dict[str, str],
+    cli_scripts: dict[str, str],
+) -> None:
+    """Both packages must point at the same CLI entry function."""
+    assert crewai_scripts["crewai"] == cli_scripts["crewai"], (
+        "The crewai and crewai-cli packages should declare the same "
+        "entry point target for the 'crewai' script."
+    )